OVA
Description
Shin Mouri, also known as Cye Mouri in certain adaptations, hails from Japan's Yamaguchi Prefecture. He descends from the historic Mouri samurai clan, tracing lineage to feudal lord Oe no Hiromoto and the renowned Motonari Mouri. Generations of the Mouri family guarded the Hagi Sea, protected the Suiko armor, and upheld traditions in pottery, martial arts, and tea ceremony. Shin's father died during his infancy, leaving him under the care of his mother—who manages the family pottery business despite a fragile heart—and his older sister, Sayoko. Sayoko later became engaged to Ryuusuke, whom Shin initially mistrusted until Ryuusuke demonstrated his worth.

At fifteen, Shin retrieved the Suiko armor from the Hagi Sea's depths during a traditional coming-of-age dive, completing the feat without oxygen thanks to an orca named Suiki. Linked to the virtue of "Shin" (Trust/Faith), the armor grants hydrokinetic powers to manipulate water into whirlpools or waves. His primary weapon, the Nijou Yari, combines trident and man-catcher functions, supplemented by a tanto dagger and claw-like tekko-kagi gauntlets, though the latter two are rarely used. His signature Chou Ryuu Ha technique fires a high-pressure water blast from the spear, amplified underwater. The armor features functional designs like retractable goggles for aquatic combat. Shin swims expertly, navigating level-four rapids or whirlpools even without armor, and communicates with marine life through mutual trust.

Gentle and conflict-averse due to his upbringing among women, Shin dislikes fighting and avoids eating fish with heads. His hobbies include tea ceremony, cooking, flower arranging, and basketball. Despite his calm nature, he exhibits fierce anger against merciless foes, invoking the Mouri clan's "three arrows" ethos of collective strength. As the oldest warrior and initially the only high-school student, he was often perceived as naive early on. He shares his closest bond with Kento, partnering frequently in missions, while maintaining respectful ties to all warriors and serving as a cautious voice during conflicts.

In the Gaiden arc, Shin journeyed to the United States to rescue Sage, battling across Manhattan and Los Angeles. He contributed his powers to summon the Inferno armor after a companion's sacrifice. During the Legend of the Inferno Armor arc, his reluctance to fight escalated into refusing to lend energy for the Inferno armor, fearing perpetual battle—a hesitation rooted in intuitive distrust of the armors' corruption, later proven valid. After nearly clashing with Kento, he temporarily left the group but rejoined upon sensing his friends' peril in Africa. There, an antagonist crystallized his armor, though he helped purify the corrupted Inferno armor through his virtue of Trust.

Later, Shin received an upgraded armor suite in the Message OVA, though its full capabilities went unspecified. Post-series, he studied marine biology in Costa Rica and visited New Orleans, acquiring a voodoo gris-gris charm containing a war spirit (loa). The charm amplified his aggression in battle, causing berserk tendencies, prompting him to seek a protective spirit like Baron Samedi to counter it. As an adult, he adopted a slightly hardened edge, rode a black motorcycle, and harbored lingering resentment toward past adversaries.