TV-Series
Description
Sasaki Kojirō, a renowned feudal Japanese swordsman, bears the epithet "History's Greatest Loser" for never winning a duel in life. This title reflects his habit of abandoning fights after mentally devising victory strategies, considering further combat pointless once achieving intellectual dominance. Trained in youth at Seigen Toda's dojo, he showcased natural talent despite apparent indiscipline—arriving late yet outperforming peers. Early duels ended in losses or surrenders, including defeat by Kagekatsu Toda that drove him to solitary wilderness training.

In the afterlife, Kojirō exists in his "Golden Age," a perpetual peak state where he continuously evolves through relentless practice. Unlike other deceased humans, he ages and strengthens indefinitely, assimilating techniques and experiences from every swordsman he encountered to forge unmatched blade mastery. His personality merges surface nonchalance with profound diligence. Though seen as lazy or cowardly for avoiding injury in duels, he possesses fierce determination, thriving against strong opponents and valuing self-improvement over fame or wealth. He honors past rivals, fighting in Ragnarok partly to memorialize them, and exhibits humility through simple tastes—eating snakes or crude pies without protest.

Kojirō's combat focus is Senju Musō ("Unmatched Anticipation of a Thousand Moves"), an innate ability to analyze opponents' physiognomy, gait, and breathing, simulating thousands of mental battles to predict attacks and refine strategies. Against Poseidon, this evolved into Manju Musō ("Ultimate Vision of Ten Thousand Moves"), incorporating environmental data like air vibrations and ground tremors to counter imperceptible assaults. His swordsmanship synthesizes styles from defeated masters, including Chūjō-ryū, Ittō-ryū, and Niten Ichi-ryū. Key techniques are Tsubame Gaeshi ("Swallow Counter"), a two-strike maneuver merging a downward slash with a 200+ km/h reversal strike to an opponent's blind spot, and Niten Ganryū, a dual-blade style activated when his primary weapon shatters, overwhelming foes with coordinated slashes.

As humanity's representative in Ragnarok's third round, Kojirō fought Poseidon. Initially overwhelmed by the god's speed and afterimages, he adapted via Senju Musō, fracturing Poseidon's trident. Empowered by Valkyrie Hrist's Volund—the nodachi Monohoshizao that splits into twin blades when broken—he secured victory with Niten Ganryū, earning humanity's first win. This triumph marked his evolution from perpetual loser to "Humanity's Ultimate Swordsman," whose lifetime of losses forged an unconquerable synthesis of human ingenuity.