Setsuna F. Seiei

Setsuna F. Seiei (刹那・F・セイエイ) is his Gundam Meister codename. He's the pilot to Gundam Exia and the main protagonist of the story in Gundam 00.


 * Real name: Soran Ibrahim
 * Age: 16
 * Birthdate: Apr. 7, 2291
 * Birthplace: Kurdish Republic (since merged into Azadistan)
 * Other known Aliases: Kamal Majirif (self-reference in episode 8)
 * Unit: GN-001 Gundam Exia

Character
He can be described as taciturn and a introverted person. He tend to reside in Japan, alone, when not on Celestial Being duties.

He believes there are key disturbances that affect peace from coming together in peace. He labeled specific people or forces a source of conflict towards the world's path to peace. He has little tolerance for diplomats and politicians, believing that their "peace talks" only prolong wars and cause more strife.

He's got a vendetta to settle and his past battle experiences stirs old feelings, increasing his combat potential as a beneficial side effect. Though he's become somewhat of an atheist, he often questions the motivations of God with people and worldly events. He idolizes the Gundams so much that he wants to embody Exia as himself, a Gundam. He's a traditionalist in honor and a martyr for his cause in Celestial Being.

In a letter to Marina Ismail, he revealed more in depth into his feelings and thinking. Setsuna wanted to understand the lesser aspects of humanity. He wanted to know why the world is filled with people with innate dark intentions and inconsiderate of other people's suffering. He wanted to find these answers with his Gundam in hopes to bring mutual understanding and peace.

His name could also be denoted to state his personality. Translated it could mean To obtain the moment. As it is (Seiei Setsuna (セイエイ・刹那) because last names come first traditionally)

Youth in Azadistan
When Soran was young, he was a Jihadist in the Kurdish Republic. Soran joined the Kurdish anti-government guerrilla organization, KPSA, that killed Lockon’s parents and younger sister. He murdered his own parents under Ali Al Saachez' "divine" influence in order to prove his devotion to God (although he now claims to not believe in any God). During a battle against Azadistan's mobile suits, his life was saved by GN-000 Gundam O.

Joining Celestial Being
Having been discovered by Celestial Being at the age of 14 (for potential as a pilot), he became a Gundam Meister for their organization. The Meister's had their doubts about Setsuna due to the fact he's considerably young. Lockon Stratos on the other hand didn't mind the age difference and even look forward in working together. After nearly two years of training and planning, Setsuna and Exia were the the first to reveal themselves to the world at the debut of AEU's Enact.

Debut at AEU
Patrick Colasour was displaying the capabilities of AEU's new Enact when Exia/Setsuna descended down. Patrick was eager to prove his strength against the intruding Gundam and drew his sonic blade at Exia/Setsuna. Exia made quick work of the Enact as Exia's GN Blade cut off all of the Enact's limbs. Setsuna then flew off to his second assignment, exposing AEU's violation of having mobile suits within their orbital elevator. While fighting with overwhelming numbers, Lockon/Dynames provided fire coverage from below to help Setsuna in combat. Everyone at the AEU show thought the Gundam was of Union or HRL origin, but was later revealed by a pre-recorded message from Aeolia Schenberg that the Gundams are part of Celestial Being.

Ceylon
There has been war at Ceylon (formally Sri Lanka) for over a century between two warring parties. All the Gundams/Meister's sortied to Ceylon for their second mission. As they were about to approach land, Lockon wanted to check-in with Setsuna, but his mind drifted towards past horrors during his youth in the Kurdish Republic as he watches live combat at Ceylon. Setsuna flew ahead of everyone, eager to end the fighting and engaged the mobile suits while Dynames/Lockon provided cover fire. After he destroyed all ground units, he and the rest of the Gundams/Meister's were heading back to their respective locations when Graham Aker appeared in his Flag. Graham thought he could capture Exia/Setsuna; Setsuna was able shove off the Flag and cut off the sonic blade from the Flag's hand before destroying the linear rifle with his beam saber and forcing the Flag to withdraw.

In a seperate intervention, the Gundams were assigned with individual missions vs group missions. Setsuna was assigned to eliminate a military base at Ceylon when he was attacked by HRL's Sergei Smirnov. Sergei wanted to test the Gundams capabilities and had his mobile suit attempt to rip off Exia's head. Sergei's Tieren grabbed Exia's head and attempted to crush it. Exia/Setsuna managed to grab his beam saber and slash Sergei's Tieren into pieces and left back to Japan.

Taribia Republic
Taribia Republic announced their withdraw from the Union. They were close to the orbital elevator and made a gambling bet that the Gundam Meister's would be lured to their country and even defend it should Union forces intervened. Celestial Being long caught on to this form of manipulation and attacked Taribia forces. Setsuna attacked all mobile units near the ground while the rest fired from above. Their intervention forced the president of Taribia to rejoin the Union to restore political and military ties between the two parties. Soon as Taribia joined forces with Union, the Gundams made a tactical retreat. While flying away, Graham Aker appared once again in his recently modified Custom Flag. He tried to shoot Exia down, but Exia retreated by going underwater.

Ali Al Saachez in Moralia
PMC/Moralia was taking arms with AEU to counter the Gundams. Setsuna along with the rest of the pilots were sortied, citing PMC/Moralia as a source conflict. While taking armed intervention, Ali Al Saachez appeared in a Enact. Because of his vendetta against Ali, Setsuna had to confirm was it the person he suspected and had him exit the cockpit. Setsuna exited his own cockpit and was angered when he confirmed his suspicions, it was indeed Ali Al Saachez. He wanted to shoot him, but Lockon/Dynames fired several intentional missed shots to have Ali return to his Enact. Setsuna never explained his reasons for endangering himself and the mission by pulling such a "stunt." After they defeated the PMC forces of Moralia, they returned to their hideout where the Meister's had a unfriendly chat with Setsuna. Lockon punched Setsuna down to the floor, demanding an explanation for his actions in Moralia, but he didn't say a word. Tieria drew his gun to force an answer and with the intention of silencing him and Setsuna drew his gun right back at Tieria. Setsuna said he has no intention of leaving his Gundam. Alleujah interjected and reminded Tieria that Veda chosen all of them and believes there was a reason for choosing Setsuna, Tieria withdrew his gun. Tieria wanted Setsuna to show him why was he chosen as a Gundam Meister. The situation was never resolved as there was a sudden terrorist attack, making demands against Celestial Being. The party split off to investigate the terrorist blackmail demands of "La Eden."

Meeting Marina Ismail
It was while he was investigating "La Eden" in Scotland (AEU), that he encountered Marina Ismail. He was chasing a suspect on motorcycle and couldn't shoot him down. The local police came and was about to take in Setsuna for questioning when Marina used her diplomatic credentials to claim he's with her party and he was let off. Marina only helped Setsuna because she thought he was a fellow Azadistan citizen. Setsuna identified himself as Kamal Majirif and Kurdish, she felt awkward after hearing that.

Although technically from Azadistan, it's only because Azadistan forcefully incorporated the Kurdish Republic into their territory. Those that couldn't conform to the Azadistan government, raised Jihad or started their own conservative political movement against the Azadistan government. Strong tensions still exist between the Kurdish and Azadistan people (religiously, politically, historically).

Setsuna wanted to leave, but Marina wanted to keep talking. She was worried about economic and political instabilities of her country might draw the attention of Celestial Being. She felt that Celestial Being were a bunch of extremists that would use force than negotiations. Setsuna responded that it was Azadistan that destroyed the Kurdish Republic. She acknowledge what her country did, but reminded him both sides tried to resolve things peacefully. Setsuna in anger reminded her that people died as the politicians talked. Marina wondered did he fought in the Kurdish Republic/Azadistan conflict six years ago and Setsuna said he continues to fight. His words frightened her, thinking he's part of the conservative party and might kill her. He told her killing her won't change anything and he revealed himself as a Gundam Meister and his code name. Setsuna warned her that if fighting continues that Celestial Being will pay a visit to Azadistan and left her frightened to the ground. As Marina continues in her political tour for economic and food aid for Azadistan, she reflected back to Setsuna's words and smirked it off, dismissing it as a bad joke. Suddenly Setsuna did a flyby with Exia right over Marina, looking down at her and flew away.

Close Call with Sergei Smirnov
HRL launched a series of e-sensors to detect the whereabouts of Celestial Being. Setsuna just returned to 'Tolemy for maintenance over Exia and was given a passive aggressive "greeting" with Tieria Erde. As they both eat lunch, it was a tense moment between the two and Christina Sierra couldn't eat between the two. By the time Christina noticed they were detected, HRL already launched several carriers and Tieren mobile units against them.

Setsuna/Exia and Lockon/Dynames was assigned to engaged the incoming force while Allelujah/Kyrios and Tieria/Virtue engaged side groups to prevent a pincer attack from several sides. Setsuna/Exia dealt with a large group of Tierens while Lockon/Dynames shot down as much as they could. In the end the Gundams prove to be too much for HRL forces to handle and Sergei Smirnov decided on a tactical retreat while they still can.

Return to Azadistan
It wasn't long Setsuna lived up to his words as he entered Azadistan. Massoud Rachmadi was the voice of reason of the conservative party. He was a political leader and outlet to those who oppose Azadistan's reforms. He was captured by unknown assailants, attempting to topple the already unstable political situation in Azadistan. Ali Al Saachez was actually the one who was hired to incite civil war between the reformists and conservative parties. Setsuna volunteered for the mission since Azadistan is his "hometown."

The Union dispatched their anti-Gundam team as they bet the Gundams are likely to appear in this political hot-spot and doubled as Azadistan's military aid. Graham and Billy bumped into Setsuna as he was investigating the local area and Graham intentionally clued Setsuna (suspecting he's from Celestial Being) off about Ali's Enact. Suspecting it was the work of Ali Al Saachez, Setsuna headed to his old Kurdish homeland to find Massoud Rachmadi.

Ali Al Saachez always suspected that Setsuna was one of the Kurdish kids he formally trained into a Jihadist. His suspicions were confirmed when Setsuna found their secret hiding place and fought. While engaging Ali, Setsuna asked his reasons for coming back since the Kurdish Republic is gone and "where is your god!?" Setsuna damaged his Enact's rifle, but pinned him down on the ground and tried to tear open his cockpit. Setsuna managed to cut off his Enact's right arm and Ali flew off. Setsuna was only a distraction while Lockon intercepted the fleeing group with Dynames.

Massoud Rachmadi was rescued and sent back to the palace where Princess Ismail resides. Setsuna entered unarmed with Exia and at first received several shots from extremists and local defense mobile suits. They eventually cleared out of his way and he dropped off Massoud Rachmadi. Marina Ismail went to confirm was it truly Setsuna and he warned her they might return again. His final words to her was to fight for the sake of her God and flew away. Graham and his team wanted to capture him, but Graham felt by doing so would only create international political complications and let him off.

Near capture in Takalamakan Desert
A war exercise was being performed by HRL, AEU, and Union for convert operation in capturing the Gundams. It's publicly announced to be a war exercise, but it was a trap. Even though the Meister's fully knew that what they were about to intervene was a trap, they entered the Takalamakan Desert knowing they might be captured or killed. Exia and Virtue were paired together while Dynames and Kyrios teamed up for aerial entry of the battlefield. While Sumeragi gave the Meister's as much plans as possible to counter the combined forces of the 3 world powers, they were worn out from excessive engagements. Ultimately all the Gundams were captured and Exia was pinned down by the mobile armor Agrissa, piloted by Ali Al Saachez. Agrissa used a plasma field to torture Setsuna and almost died from excessive electrical shock when Gundam Throne Drei appeared. The Throne Gundams appeared and rescued everyone to safety. They returned to the 'Tolemy, they questioned if they are members of Celestial Being as they never heard of their existence.

Team Trinity
The Meister's were given coordinates for a meeting by the Throne Gundam Meister's and they agreed to meet on board the 'Tolemy. The Trinity Siblings confirmed they share their objectives about ending all conflict. Nena wanted to find out who was the pilot of Exia, Setsuna identified himself as the pilot and Nena went at him for a kiss. Setsuna didn't react well to Nena's kiss and shoved her away. Tensions raised when Michael came to defend his sister and pulled out a sonic blade. Johann had to control Michael to calm the situation down. The Trinity's gave limited information about themselves besides sharing their ideals and running missions independent of theirs. Setsuna wonders if they are true Gundam Meister's, Tieria also concur with Setsuna's suspicions.

The Gundam Meister's held back and allowed Team Trinity perform their missions; Setsuna became more and more dissatisfied as they indiscriminately hurt civilians and execute total annihilation tactics in their missions. Setsuna and his group became more suspicious when they discovered their GN Drives are considered imitations and not real "solar furnances." The last straw for Setsuna was when Nena indiscriminately attacked Louise's family. He sortied Exia and identified the Throne Gundams and Meister's a source of conflict.

War against the Trinity's
While the Trinity's were flying to their next mission, Setsuna fired three unwarned shots at them. He cited them as sources of conflict and aimed at Throne Drei, but Throne Zwei intervened and fended him off. Johann tried to reason with Setsuna, but Setsuna doesn't recognize them as true Gundam Meister's and Johann had Michael retaliate. Michael launched 6 of his GN Fangs, but Setsuna destroyed them all with his GN Blades. Michael had 2 GN Fangs reserved and launched them. Setsuna wasn't able to anticipate them, but then a powerful GN particle blast wiped the last two. The blast came from Virtue and Tieria decided to team up against the Gundam Thrones.

While fighting, it was the first time Exia and Virtue to execute battle formations (as the pilots never once got along). Virtue engaged Drei and Eins while Exia engaged Zwei. It wasn't long that Dynames entered the fight and the Thrones decided to regroup and retreat. Before they retreated though, Johann revealed classified information pertaining Lockon's and Setsuna's past. Johann revealed to Lockon that the very group that were responsible in his family's death is also linked with Setsuna. Johann explained that Setsuna was really Soran and that he was once part of the same terrorist group that killed his family, KPSA. The Throne's flew off, but left Lockon angered against Setsuna.

The three Gundam Meister's "parked" their mobile suits and had a personal chat, with Lockon pointing a gun at Setsuna. Lockon wanted a good explanation behind Setsuna's past and a reason not to kill him. Setsuna revealed that he was formally trained to be a guerrilla by Ali Al Saachez, leader of KPSA. He admitted at that time he was immersed in his own world of God, but now no longer believes in God in this world. He explained that time when he exited out of his cockpit in Moralia was to confirm Ali and wanted to know if there was God within him. Lockon wanted to know what are Setsuna's future plans and his intentions with Exia. He reaffirmed that he believed in their cause and wouldn't mind if Lockon killed him if he continued their goals to end conflict. Soran wanted to continue to be a Gundam Meister, Setsuna F. Seiei, for he is a "Gundam." Lockon withdrew is gun because he couldn't shoot a dumbass like him, a "stupid Gundam." Setsuna considered that as praise and the three Meister's shared a good laugh.

It was around this time that the 3 world powers (AEU, Union, and HRL) were brought down to their knees. They no longer had the necessary ability to face the Gundams and the 3 world powers reluctantly considered the idea of surrendering to Celestial Being. The Celestial Being traitor, Laguna Harvey, made calls to 3 world powers to obtain 30 GN-X's in Antarctica. With these new mobile suits in their hands, the world governments united their military might as the UN Forces, declaring their united objective of taking down Celestial Being. They called their plan, "Operation Fallen Angels."

Fall of Celestial Being
The UN Forces quickly made use of their GN-X's. They managed to fend off the Trinity's and their Throne Gundams. The Gundam Meister's and the crew of the 'Tolemy were surprised that GN technology fell into the world's hands. The UN Forces now are on the offensive against Celestial Being. It wasn't long the 'Tolemy was also targeted and the Meister's sortied to defend their ship. While fighting, their Gundams suddenly shutdown. They didn't know that Alejandro Corner was hacking and controlling Veda during their battle. Sumeragi was able to anticipate such an event and switched their Gundams to independent operation systems vs linked to Veda. Setsuna cried out for Exia to activate and Exia reactivated. He was able to fend off the GN-X's to a tactical retreat, but the battle wounded Lockon and badly damaged Dynames.

While "Curse GN-X Squad" was confronting the Throne's, Setsuna on board 'Tolemy wondered if how things are happening is considered right. He observes that the Trinity's and the UN Forces were only increasing conflict. Setsuna wanted to confirm the state of things and decided to head down. Lasse Aeon teamed up with Setsuna for the first time, riding the GN Combat (or Assault) Container for atmospheric re-entry.

During Setsuna's entry to earth, Ali Al Saachez appeared before the Trinty's claiming to be an ally. When Johann asked about Laguna Harvey, Ali responded with a gunshot. He killed Micheal with a handgun and subdued Johann. Ali wanted to fight Johann in mobile suit combat and let him off to pilot Gundam Eins. Ali somehow bypassed the biometric scanner of Throne Zwei and used Zwei against Eins. Johann suspects he somehow altered the system as only Michael was able to pilot Zwei, he destroyed Johann/Eins. Ali was about to finish off Nena when Setsuna intervened. Setsuna was surprised to see that Ali somehow got his hands on a Gundam and the two fought. Even though Exia was well armed, Ali still managed to defend himself against Setsuna very well. During this time, Alejandro Corner was putting his final plans into work to control Veda and just killed Aeolia Schenberg. Schenberg's "system trap" activated and removed the limiters on Exia to execute the Trans AM system. Just as Ali was about to strike Exia from behind, Exia goes into a high speed frenzy. Exia's Trans AM was too much for Ali and he fled.

Setsuna reported his findings to the rest of the crew and headed back to 'Tolemy. It was around that time that the UN Forces attacked again with their GN-X's. Setsuna was returning to space while the rest of the Gundams were busy with UN Forces. By the time Setsuna returned to space and sortied, the battle was near end. He went into Trans AM mode to make up lost time and found Lockon Stratos floating in space. Setsuna tried to rescue him, but the damaged GN Cannon nearby exploded and killed him. Setsuna was distraught over Lockon's death, but returned to 'Tolemy to prepare for another round against the UN Forces. Tieria was upset at Lockon's death and blamed Setsuna for heading to Earth and not making it back in time to save Lockon. Sumeragi had to settle things down between the two as they need to prepare for another fight. It was while looking over tactical data over Lockon's final moments that he realized that Lockon died in his quest for revenge against Ali Al Saachez. The crew got ready for battle, but to their surprise a golden GN Mobile Armor with 7 GN T(au) Drives appeared. Alejandro Corner was piloting the Alvatore and used it to help destroy the 'Tolemy, Kyrios, and Nadleeh. All the Gundams have now been damaged beyond repair, only their GN Drives survived.

Climatic Showdown
The only team still able to fight was Lasse Aeon in GN Arms and Setsuna in Exia. During the early part of the battle, they breached through the UN Forces's offensive line with the Combat (or Assault) Container to deal with Alvatore. They blasted the Alvatore with their GN Cannons at full strength, but the super GN Field was so dense and powerful that it repelled any incoming fire. Lasse rammed the container with GN Field against GN Field in hopes to penetrate deep enough to damage the mobile armor, but to no avail as the mobile armor unleashed its grappling arms, splitting the hull apart. Lasse had to eject the container with Setsuna for mobile suit against mobile armor.

Lasse and Setsuna doubled teamed against Alejandro, but couldn't penetrate the super GN Field. Alvatore deployed its own version of fangs against Setsuna. Lasse switched to GN Armor and Exia docked for a mobile armor against mobile armor combat. In GN Armor, Setsuna and Lasse was able to destroy all the GN Fangs and disable Alvatore's grappling arms. Alvatore severely damaged the GN Armor section (Lasse Aeon is presume dead) and Setsuna rammed the GN Blade of GN Armor and disabled Alvatore's GN Field. Without the GN Field in the way, Setsuna made quick work of Alvatore and destroyed the mobile armor.

Second Round
While Setsuna was trying to confirm Lasse's condition, a beam fired into his direction. The upper section of Alvatore's armor unfolded to reveal a mobile suit, the  Alvaaron. Alejandro ejected the lower section of Alvatore and engaged Setsuna in mobile suit combat. While firing at each other, Alvaaron's wings shifted forward to charge GN particles to fire a powerful particle beam. Alejandro thought he vaporized Exia from the blast, but Setsuna survived by executing Trans AM. Setsuna was able to use its GN Sword to penetrate through Alvaaron's GN Field and damaged Alvaaron. Setsuna quickly cut through Alvaaron with all of Exia's blades, the suit soon overloaded and killed Alejandro in the explosion. Setsuna barely had a moment to rest when another GN mobile suit appeared.

Final Round
Graham Aker appeared in his GN Flag. Graham's flag was heavily modified to adapt to space combat as well as utilizing a GN Tau Drive. Graham engaged Setsuna to fulfill his vow of revenge for Howard and Daryl. Graham was able to cut down Exia's left arm and decapitate Exia's head. Setsuna too decapitated his GN Flag's head and cut off his lower torso and legs. In the final charge, both opponents severely damaged each other's suits and caused a massive red and green GN particle explosion. Setsuna was wounded, but unclear was it fatal as the beam saber only grazed him on the right side of his cockpit. As Setsuna/Exia gravitated towards Earth, Marina Ismail was reading a message she recieved from Setsuna.

Letter to Marina Ismail
Setsuna sent a message to Marina Ismail before the climatic battle between UN Forces and Celestial Being. As Exia/Setsuna floated in space towards the gravity of Earth, she reads the following:

Marina Ismail,
 * By the time you read this...I'm already gone. Armed interventions to put and end to war, I'm unable to do anything but fight for Celestial Being. You taught me what it means to fight back then, just like Gundam. I wanted to know why our world is so terminally distorted. Where did that distortion come from? Why there are people who are unconsciously evil? Why people don't know that their evil hurts others. Why is humanity an existence which only conflicts with itself? Why are there people who rule and those who are ruled? Why do we wound each other? In spite of all this, why do people go on living like they do? I wanted to ask you...please think of an answer if we may meet again. That being the case, I will seek out the same thing on a different path than yours. Down the path towards mutual human understanding for the answer. I'll keep looking for it, together with my Gundam.

Four Years Later
Four years has passed since the fade of Celestial Being. Various characters that might have been presumed dead are confirmed very much alive and well. Setsuna's fate is still unknown, but Exia's (suggesting Setsuna was recovered, at least his body) core solar furnace has since been installed to Double O Gundam. Being the protagonist of the story, he's likely to be alive and well.

Kingdom of Azadistan
When the Kurdish Republic still existed, Azadistan started a war with their neighboring middle eastern country. Azadistan was better equipped in weapons and eventually the Kurdish Republic was destroyed and since merged with Azadistan. While people of Kurdish descent were granted citizenship in Azadistan, they weren't welcomed by the Azadistan locals. Setsuna has mixed feelings when it comes to Azadistan's past actions against the Kurdish Republic due to the deaths in his life.

Marina Ismail
Marina met Setsuna by chance because she thought she was helping out a fellow Azadistan countrymen. To her mistake she helped out citizen that was formally part of the Kurdish Republic, making conversation awkward. Though not true friends, Setsuna has respect for her as a person trying to find peace and solutions to Azadistan's development issues. Setsuna revealed his code name identity as a Gundam Meister and warned her Celestial Being would come if conflict continues there. During Setsuna's return to Azadistan, he helped her restore peace by rescuing their conservative leader, Massoud Rachmadi. He returned not long in the middle of the night, asking her "why is the world distorted (or twisted, depending on translation). Before he sortied on his final mission, he wrote a letter to her. Marina was genuinely concerned and was touched by Setsuna's possibly post death letter.

Massoud Rachmadi
A leader to the conservatives that Setsuna brought back from the clutches of Ali Al Saachez. He flew in with Exia, un-armed, and in good faith returned Rachmadi.

Ali Al Saachez
Former leader of the terrorist organization KSPA, it was he who brainwashed Setsuna as a child and turned him into a child soldier under the guise of religion. As such, he has greatly impacted Setsuna, causing him to harbor a general disbelief in religion and peace talks. He trained Setsuna in an undisclosed martial art, and this in turn is used by Setsuna mainly when he pilots the Exia. Having met on the battlefield, Setsuna initially exited his cockpit to confirm his opponent was Ali, which brought him under criticism from his fellow Meisters. Meeting at other times, Setsuna fiercely battled the man, but was never able to defeat him.

Japan
It's unclear why has Setsuna chose Japan as his "homebase" of operations; he lives alone with a simple bed where he often reflects or exercise until the next mission.

Saji Crossroad
He's neighbor's with Saji Crossroad and while the have idle conversations,

Louise Halevy
She only met Setsuna through her boyfriend, Saji.

Celestial Being
Note: The dynamics behind all relationships within the series aren't completely defined. Only what was observed in the series was described.

Aeolia Schenberg
Though Setsuna has never met Aeolia Schenberg, he believes in his philosophy and served his organization as a Gundam pilot. It was Aeolia's system trap that activated Trans-Am that saved Setsuna from Ali Al Saachez.

Veda
Veda was the AI that approved of Setsuna to be the pilot of Gundam Exia for Celestial Being. Though Veda and Setsuna have no real bond with each other, Veda is interlinked with Exia. Whatever Setsuna does or goes, if he's using Exia, someone will know.

Lockon Stratos
Lockon was something of an older brother to Setsuna during the first half of the series. Often working together on missions, Setsuna felt close to Lockon. Later on, it was revealed that Lockon Straos' parents and sister were killed by a KSPA terrorist attack, the same organization that Setsuna was a part of with Ali Al Saachez. Lockon confronted Setsuna over the situation, drew his sidearm and demanded justice, to allow him to avenge his family. Setsuna did not attempt to dissuade Lockon from his intentions, stating that he believed that Lockon would change the world in his stead. However, Lockon noted that the real enemy was Ali Al-Saachez, not Setsuna. Later on, during the GN-X's assault on the Ptolemaios, Lockon was injured after a beam saber assault struck his cockpit while defending Tieria Erde. Injured almost gravely, Lockon lost his right eye, mainly used for targeting during sniping. When a second assault by the GN-Xs occured, Lockon sortied in the repaired GN-002 Gundam Dynames. Ali Al-Saachez, who was piloting the hijacked GNW-002 Gundam Throne Zwei, engaged Lockon in combat and both defeated each other near simultaniously. Setsuna, who was returning from Earth, attempted to retrieve and save Lockon. However, the GN Arms component nearby Lockon's drifting form exploded before he could be reached, presumably killing Lockon. Setsuna mourned Lockon's death along with many other members of the crew.

Tieria Erde
Tieria and Setsuna were never exceptionally close. Even in the beginning, Tieria disapproved of Setsuna's being chosen to become a Gundam Meister. Throughout the series, Tieria and Setsuna are loathe to work together, and Tieria typically considers Setsuna to be unfit for his position. However, the two have shown capacity to be considerable allies, notably during the desert assault of episode 15. At this point, it was a likely possibility that the two could become friends, but upon Lockon Stratos' death, Tieria lashed out at Setsuna, blaming him for Lockon's death. Sumeragi Ri Noriega did intervene, but the possibility of the two becoming good friends has yet to be seen.

Allelujah Haptism
Setsuna and Allelujah did not seem to interact very much, apart from the typical battle forecast meetings by Sumeragi Li Noriega in which both had to be present simultaniously. Neither were seen to be dismissed as a pair during missions, such pairings instead being Lockon/Setsuna or Tieria/Allelujah.

Sumeragi Lee Noriega
As commander of tactical operations, Setsuna always carry a planned assault from Sumeragi. Interestingly it's the other Gundam Meister's that are more strict with Setsuna than herself. They maintain a friendly/professional relationship.

Christina Sierra
Though they aren't close, Christina covered up for Setsuna when he used Exia to visit Marina Ismail in Azadistan. They're in constant contact only during missions because she's one of tactical coordinators. She wouldn't bother talking to Setsuna if it weren't business related.

Feldt Grace
Feldt and Setsuna did not interact much prior to Lockon's passing. Even afterwards, the two did not seem to grow considerably closer. However, they did share a moment while standing at the cockpit of Lockon's Gundam Dynames after his death. There, Feldt shared that she had written a letter to Lockon, and told his Haro to stay with him and keep him from growing lonely. She then asked Setsuna if he wanted to write a letter to anyone, but he declined.

Lasse Aeon
Lasse and Setsuna, late in the series, were paired as partners given Lasse's capability of piloting the GN Arms Type E. Setsuna seems to respect Lasse, and vice versa, as the two have proven capable pilots when working together. They did not seem exceptionally close, but Setsuna did appear somewhat panicked when attempting to confirm Lasse's condition after the cockpit of the GN Arms Type E exploded during the final battle with Alejandro Corner's Alvatore mobile armor.

Lichtendahl Tsery
They have a friendly/professional relationship, however Setsuna was never the talkative time so there was little interaction between the two.

Ian Vashti
Setsuna's idolizes his Gundam and while he might not show his gratitude to Ian, he's greatful for Ian's maintenance and upgrades for his Exia. They have a professional/friendly relationship.

Joyce Moreno
Though the Ptolemy's doctor, he doesn't appear to have any contact with Setsuna. They likely had a professional/friendly relationship.

Johann Trinity
Johann maintains a professional attitude with Setsuna, but he's not above using mind tricks to disrupt the unity with the other Meisters when he revealed Setsuna's link with Lockon's vengeance.

Michael Trinity
He dislikes Setsuna strongly because Nena fell in love with him. He doesn't understand why his sister would like Setsuna, but he "itches" to eliminate him.

Nena Trinity
She was impressed by Setsuna's reckless actions and on the first meeting face-to-face, she went at him for a kiss. Setsuna however didn't like Nena's kiss and shoved her off. When Ali Al Saachez nearly was about to end her life, Setsuna intervened to save her life. It is unclear whether Setsuna has feelings for Nena.