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His Personal Name is Laughing Fox (ラフィングフォックス, Rafingufokkusu?).
He was a platoon leader of the Eighty-Sixth Strike Package's Spearhead Squadron and the artist of the squadron member's Personal Marks. He is currently on indefinite leave following the Mirage Spire Operation.
Theo has the golden hair and green eyes of a Jade. He is slender and—compared to the other boys—fairly short at 165 cm tall. Like the other members of Spearhead, he wears desert camouflage combat fatigues scavenged from the Republic's surplus stocks. He later switches to the Federacy's steel-colored panzer jacket uniform.
After the events of Gun Smoke on the Water, Theo loses his left hand.
Theo is described as guileless and brutally honest in his thoughts. Sarcastic and blunt in his words and humor, Theo has difficulty restraining himself from speaking his mind. This is most evident in his tirade against Lena following Kaie's death.
Theo keeps a sketchbook that he often draws in as a pastime.
Theo was born on April 20th 351 in the Republic of San Magnolia. His ancestors migrated from a southern nation called Elektra two hundred years ago. Much like the other Colorata, he and his family were sent to the internment camps of the Eighty-Sixth Sector and forced to fight the Legion.
Theo holds a grudge against most Alba, but is willing to accept that there are some honorable ones due to a past experience in his first squadron. His first squadron was lead by an Alabaster former soldier from the decimated Republic Armed Forces. Theo and the rest of his squadron hated their leader, believing him to be a self-righteous pig that could retreat to the Eighty-Five Sectors once things went south. He didn't run away however; the leader died in a sortie where he refused to retreat to allow the other Processors to escape. The dying squadron leader's final words to Theo had a profound impact on him; Theo adopted the leader's Personal Name and Mark of Laughing Fox.
Theo's unit—the Laughing Fox—is the most orthodox of the team, being left in its standard weapon configuration. The same cannot be said about his piloting style. Theo is adept at using the grappling wires of his unit, leaping and swinging through the air between trees or buildings. He often attacks from a vertical surface, such as the side of a building, to pierce the thinner top armor of the Legion. This is a strategy that takes advantage of his excellent spatial perception and the fact that the heavily armored Legion such as Löwe and Dinosauria possess major weak spots on their top armor. Some Legion units like the Löwe also have difficulty elevating their weapons, reducing the danger Theo faces when he attacks from above.
Theo is the artist of the Spearhead Squadron's Personal Marks, including Shin's, Lena's, Raiden's, Anju's, Kurena's, and his own mark. He also drew the portraits of the squadron's Handlers back in the base of the First Ward. He is skilled in different techniques such as pencil sketching and painting.