OVA
Description
Mouri Shin, born March 14, 1973, in Yamaguchi Prefecture facing the Sea of Japan, belongs to the historical Mōri samurai clan, descendants of Ōe no Hiromoto and including the famed Mōri Motonari. Generations protected the Hagi Sea and safeguarded the Suiko armor while practicing pottery, martial arts, and tea ceremony. Shin's father died young, leaving him to be raised by his mother, who had a weak heart, and his older sister, Sayoko. Sayoko later became engaged to Ryuusuke, whom Shin distrusted initially until Ryuusuke proved himself. Growing up near the ocean made Shin an exceptional swimmer capable of deep dives without oxygen. He developed the ability to communicate with marine animals, forming bonds of mutual trust, especially with an orca named Suiki. At age 15, he retrieved the Suiko armor from a seabed crevice during a traditional manhood rite, learning afterward his mother knew its legend.

Characterized by gentleness, politeness, and a strong aversion to conflict, Shin becomes formidable when angered. He deeply values trust, embodying the virtue "Shin" (faith/trust). As the oldest warrior, he was initially the only high school student. His hobbies include tea ceremony, cooking, flower arrangement, English conversation, and he excels at basketball. He dislikes eating fish with heads attached, likely due to his marine connection. Raised primarily by women, he displays considerate and nurturing traits alongside occasional teenage mischievousness. He struggles with loneliness despite group camaraderie and expresses concern pragmatically, sometimes perceived as sternness. During later conflicts against the Dynasty, he questioned the necessity of fighting, particularly resisting his role when innocent lives were at risk.

In the Dynasty War, Shin fought using his aquatic abilities and Suiko armor. During the Gaiden arc, he traveled to the United States to locate the captured Sage. He later helped defeat Shikaisen and contributed energy to summon the Inferno armor. In Kikoutei Densetsu, his reluctance intensified during the conflict with Mukala. After Kento and Rowen advocated accepting their destinies, Shin refused and separated from the group. He later reconciled, traveling to Africa to aid his friends. There, he helped heal their drained energy and witnessed Mukala's purification. His armor was temporarily absorbed by the Black Inferno before the collective virtues of the warriors destroyed both Inferno armors. By the time of Message, Shin had accepted his responsibilities, receiving new armor from Suzunagi with unspecified capabilities. He grew from 164 cm to 174 cm and 54 kg to 63 kg between the TV series and Message.

Shin wears the Suiko (Torrent) armor, representing water and trust. It draws power from any water source and features a helmet face guard forming goggles underwater. His primary weapon is the Nijou Yari, a spear combining trident and man-catcher functions. A tanto dagger is sheathed on the back of his shoulder, and claw-like tekkotsume gauntlets adorn his forearm. His special attack, Chou Ryuu Ha (Super Wave Smasher/Crusher), generates a pressurized water stream from the spear tip, amplifiable underwater or upgraded to Choudan Dou Chou Ryuu Ha (Ultra-Ballistic Super Wave Crush). The armor enables water manipulation for whirlpools or waves, enhances swimming prowess allowing navigation through level-four rapids, and facilitates communication with marine life for assistance or reconnaissance.

Shin shares close bonds: Ryo Sanada relies on his loyalty; Kento Rei Faung partners with him frequently, with Shin intuitively understanding Kento's reactions; Sage Date shares his thoughtful approach; and Rowen Hashiba collaborates with him when needed. Beyond this group, he maintains deep concern for his mother's health due to her heart condition. His relationship with sister Sayoko and brother-in-law Ryuusuke evolved from initial friction to trust.