Jin Tsurasawa is a central figure in the narrative, distinguished by his striking appearance with pale skin, white hair, and brown eyes. He is the son of a politician, a background that has shaped his sophisticated and calculating demeanor. In contrast to his partner, Jin is smooth-talking and charming, often presenting a more communicative and outwardly agreeable front. However, this loquaciousness is deceptive, as he rarely, if ever, fully reveals his true thoughts or intentions to others. Beneath the charming exterior lies an incredibly intelligent and highly skilled individual, particularly noted for his exceptional control over his mecha, known as a Gladiator unit.

Jin begins the story as a deserter from Phantom, a formidable group of mercenaries. He is the mastermind behind the rescue of a young girl named Sana, and together with his companion Jo, he takes on the role of her protector. In this capacity, Jin acts as the leader of their small group, devising plans and directing Jo during combat situations. He often behaves in a manner that appears fatherly and caring toward Sana, displaying a charming and ambitious side that makes his betrayal of his former organization seem altruistic.

As the story unfolds, the true depth of Jin's motivations is revealed to be far more complex and self-serving than it initially appears. His stated reason for protecting Sana, revenge against the military, is ultimately shown to be a temporary motivation. In a critical twist, it is disclosed that Jin is actually aligned with the military and was never a genuine ally to his companions. He is responsible for the murder of Sana's father and has no real emotional attachment to either Sana or Jo, viewing them solely as tools to facilitate the achievement of his own goals. This duplicity extends to a deep-seated envy he holds for his partner, Jo, particularly regarding Jo's natural and superior ability to control his mecha.

Jin Tsurasawa's primary role in the story is that of a deuteragonist whose hidden agenda drives much of the central conflict. He is the architect of the initial escape that sets the plot in motion, yet his ultimate allegiance creates a dramatic irony that defines the trio's journey. His key relationship is with Jo, his former partner in Phantom. While they fight side-by-side, Jin's feelings are poisoned by jealousy and a cold, utilitarian view of Jo as a mere asset. His relationship with Sana is built on a lie, as he presents himself as a protector while secretly being complicit in the forces hunting her. This deception culminates in his significant character development: the unmasking of his false persona. He is not a reluctant hero but a calculating antagonist who uses a facade of heroism for personal gain, revealing a ruthless and ambitious nature that prioritizes his own objectives over the lives of those he claimed to defend. His notable abilities include his acute intelligence, strategic planning, and masterful piloting skills, all of which he employs not for the mission of protection but for the execution of his hidden, personal agenda.