Matilda is the commander of the Medea Supply Unit. In accordance with General Revil's special order, she continues to send a large amount of supplies to White Base without any escort, using only Medea transport planes in a daring formation. She has a strong belief in her job, and feels a strong attachment to White Base. Her supplies are an oasis that quenches the thirst of the White Base crew, who are exhausted from fighting alone and without support. Due to her stunning beauty, she became the dream girl of many of the young male crew members staffing the White Base, especially the young Amuro Ray.
When the ship reached Asia, Matilda gave the White Base orders to head to Ukraine to take part in Operation Odessa, a large-scale military operation to wrest control of the mining facilities at Odessa away from the Principality of Zeon. However, en route to participate in the battle, the White Base was attacked by the Zeon ace pilot trio, the Black Tri-Stars. In order to protect the White Base, Matilda rammed her Medea into one of the Black Tri-Stars' Doms, in an attempt to knock it down. But Dom pilot Ortega hit back, smashing the Medea's cockpit, causing the transporter to crash and explode, killing Matilda instantly. Matilda Ajan was listed as killed in action on November 6, U.C.0079.
Afterwards, Amuro meets Matilda's fiancé Lieutenant Woody Malden in Jaburo, and apologizes for not being able to protect her. Woody forgives him since it was war and because she died doing what she loved the most, protecting her friends in the White Base.
Matilda appears in the novelization of Mobile Suit Gundam in the same capacity as she did in the anime. However, unlike her anime counterpart, it is assumed that Matilda survived the One Year War.