Tatsuuma Ushiyama, dubbed "Ushiyama the Undefeated," honed unparalleled judo prowess across a decade of combat in Mikawa province (modern Aichi), never suffering defeat. His life fractured violently after an affair with his master’s wife culminated in killing his mentor and maiming ten fellow students, leading to incarceration at Abashiri Prison.

Towering at 188 cm with bone-crushing strength, Ushiyama wielded a blade-resistant skull and a physique capable of subduing warriors, horses, and bears. His combat mastery extended beyond opponents—crushing limbs with bare hands and dismantling walls mid-chase through judo throws.

Post-escape, he allied with Hijikata Toshizou, lured by the promise of Ainu gold. Though wealth-driven, he grew into Hijikata’s most reliable enforcer, aiding in recruiting fighters like Zenjirou Shibukawa and clashing with rival factions. Ushiyama openly challenged Hijikata’s grander ambitions yet upheld steadfast loyalty, balancing pragmatism with the group’s objectives.

His persona married brutishness with surprising tenderness. An insatiable libido drove him to frequent brothels, a vice Hijikata permitted to harness his focus. Yet he fiercely shielded children and sex workers, exemplified when he brutalized Ueji Keiji for harming a child. Bonding with Asirpa, he earned the jesting moniker "Professor Penis," later sharing cultural exchanges and mutual trust.

Pivotal acts included propping up collapsing structures to rescue allies like Tanigaki and Inkarmat, surviving through sheer tenacity. His final defiance saw him interpose himself between Asirpa, Shiraishi, and a grenade blast—a fatal sacrifice revealing buried selflessness beneath his rugged exterior.

Across conflicts, Ushiyama embodied contradictions: a mercenary brawler governed by primal urges yet bound by loyalty and sporadic compassion. His death closed the arc of a warrior defined by unyielding physicality and multifaceted motives.