Personality & Character
It is hard to determine Desil's true personality and character. When he first met Flit, he seemed like a typical cheerful and innocent young boy who had a playful streak. However after stealing the Gundam he changes. While still playful he no longer seems innocent and cheerful, instead he gives off the impression of a cat playing with a mouse, a predator toying with prey for his own amusement. He also appears more mature, far more mature than a young boy should be. Desil also doesn't care about a person's life as shown in episode 14.
As an adult, Desil has become more insane. He shows jealously of his younger brother, Zeheart Galette of being commander of the Vagan force. Also, he wants revenge on Flit since their last battle.
Skills and Abilities
As an X-Rounder, Desil possesses the same abilities similar to Flit and Yurin L'Ciel, which he uses effectively when he piloted the AGE-1 Gundam, surprising both Flit Asuno and Woolf Enneacle. Despite his young age he is shown to be a very capable pilot to the point where he can even pull difficult stunts while fighting the UE mobile suit types when he hijacked the Gundam from Flit.
Meeting Flit Asuno
Desil Galette is first met when Flit almost runs him over with a scooter. Desil had a small injury that Flit offered to take care of back on the Diva. At the time this event seemed to be a coincidence, however events indicate that Desil set everything up so he could get the opportunity to observe Flit and the Gundam.
After Flit treats the wound Desil plays a game of tag by bouncing around the gravity-less room until Flit caught him. After that he asks to see the mobile suits on the ship, to which Flit agrees seeing nothing wrong with a young boy being interested in mobile suits.
Hijacking The Gundam
When the UE presence was made known Desil stole the AGE device from Flit and used it to activate the Gundam which he piloted out into space. There he engaged the Gafran, however from Flit's eyes it appeared Desil wasn't serious and was only playing around as the Gundam zipped around the battlefield in a manner similar to Desil's earlier game. Still Desil proved to have amazing skill and could read the Gafran so well he knew what they were going to do. After the battle Desil took the Gundam to an isolated section of the colony's port, with Flit following in a Genoace, where he returned both the AGE device and the Gundam to Flit saying that he expected more from them.
Later Desil could be seen observing the Diva through a window, saying how he was disappointed with Flit and the white mobile suit. Then several cloaked figures appeared who admonished Desil, citing how he was a member of EDEN and that he shouldn't be associating with "these" people. Desil apologized and explained that he thought they would be interesting.
Observing The Battle
When Flit and Woolf were battling a Zedas outside the Madorna mobile suit workshop Desil could in a very well furnished room observe the battle remotely, during which he gave the Zedas orders to retreat since he found the battle uninteresting.
Battle Outside Fardain Colony
After the UE retreated from their attack on Fardain, during which the Zedas was finally defeated by the AGE-1S Gundam AGE-1 Spallow, Desil could be found in his room once more, though this time he had trashed it in a fit of anger. He frustratingly calls out that he is stronger than this.
Battle of Ambat
When the battle is well under way, Desil heads out in his xvv-xc Zedas and engages Flit in the AGE-1S Gundam AGE-1 Spallow, shocking the latter that Desil is aligned with the UE. During the fight, Desil clearly has the upper hand due to his X-Rounder abilities, and all the while taunts Flit. When Flit begins to match Desil, the young boy reveals his trump card, the xvb-xd Farsia, piloted by none other than Yurin. Desil, via his X-Rounder abilities, controls the Farsia, forcing Yurin to fight, and double teams Flit, cruely laughing at Flit's hesitance to fight Yurin. When Flit begs Desil to stop, Desil complies by going in for the kill, however Yurin gains control of the Farsia at the last second, and takes the blow meant for Flit, resulting in her death. A grief-stricken Flit asks Desil why Yurin had to die, to which an indifferent Desil responds that there is no reason, and all that happened was that he lost one of his "playthings". This enrages Flit, who now fully awakens his X-Rounder abilities, and attacks Desil and easily rips apart the Zedas. Desil, unable to keep up with Flit, quickly loses his composure and breaks down into tears, unable to accept that he has lost. Flit leaves Desil to float in space, as the young boy manically screams that he did not lose.
Awakening From Cold Sleep
The Invasion of Big Ring
Later in the invasion of Big Ring, Desil revealed himself along with his new mobile suit Khronos, eliminating a few enemies. When Asemu's AGE-2 Gundam AGE-2 Normal was nearly defeated by Zeheart's Zeydra, Flit appeared with his AGE-1F Gundam AGE-1F Flat. During the fight with AGE-1, Desil recongized the pilot in the cockpit was Flit and which Flit recongized Desil as well. They had a deadly fight each other with anger. At the end of the battle, AGE-1F Gundam AGE-1F Flat cut off the body part of Khronos (resulting the defeat of Desil). Desil was eventually forced to retreat by his brother Zeheart with his unhappy mood.
The Assault on Diva
Later, Desil convinced Leo Luis, Lessie Adonel and Mink Leiden, members of the Vagan Magicians 8 X-Rounder Corps to join him for an assault on the Diva, intent on settling his revenge with Flit. However, his plan was thwarted, thanks to Flit keeping him at bay, thanks to using the Diva's armaments to keep Desil mobile, while at the same time not provide Desil an opportunity to attack. Desil and Mink were then forced to retreat thanks to Asemu Asuno and Woolf Enneacle eliminating Leo Luis and Lessie Adonel, respectively.
Battle of Nortram & Death
During the battle of Nortram, He was determined to defeat Flit Asuno, but was intercepted by Asemu Asuno and Woolf Enneacle. Desil battled Woolf fiercely while at the same time, battling Asemu, Desil had to turn the tables on Asemu by using his ability to take control of the other two members of the Vagan Magicians 8 X-Rounder Corps, Zafar and Ned, and pinning Asemu's Gundam tight in between the mobile suits, allowing Desil to go in for the kill, before going after Flit Asuno, but Woolf Enneacle fired his shots at the two Vagan X-rounder mobiles, getting Asemu out of there, and the moblie suits exploded. This allowed Desil to move in and backstab Woolf Enneacle's G-Bouncer and sent Asemu into a deep thirst for revenge. Desil was shot at by the Genonace and Adele mobile suits and retreated, after Woolf Enneacle's death, he slashed the Diva team mobile suits that Arisa, Max and Obright Lorain were piloting rendering them useless.
Asemu then charged at Desil without hesitation and brutally started attacking Desil with pure determination and desire for revenge after Woolf's death. Without any help from Zeheart, he had to fight Asemu, he kept firing his shots at Asemu, but kept missing, Desil wondered why he couldn't read Asemu's movements even though Asemu wasn't an X-Rounder like him, Desil missed his swipe at Asemu and he had parts of his Khronos mobile suit hacked and slashed away, while Asemu shouted his name to Desil, Desil shouted he couldn't lose and his Khronos exploded, killing him for good.
- Desil's Voice Actress, Ayahi Takagaki also voiced Feldt Grace from Mobile Suit Gundam 00.
- Desil is the youngest person ever to pilot a Gundam in the overall metaseries.
- As an child, his appearance looks like Devine Nova from Mobile Suit Gundam 00. As an adult, he looks like Bring Stabity.