Anji is a fallen monk turned warrior fighting alongside Shishio, driven by a deep wound: the Meiji government's inaction during the anti-Buddhist purge that destroyed his temple and killed five orphaned children he'd been raising. Those kids came from families that resisted the Meiji restoration and were casualties of the resulting conflict. Though he's abandoned monastic life, Buddhist beliefs still run through him—he's convinced that cleansing the world of evil is his path to salvation, and he'll ally with evil itself to achieve it. His title, "The Bright King," references Acala, one of the Five Wisdom Kings, a figure who destroys delusion and protects the faith. That's how Anji sees his own purpose.
He's the third strongest member of the Juppongatana and probably the most merciful. He and Shishio have an agreement: Anji gets to decide who lives and who dies. Rather than fighting with a sword directly, he relies on his signature technique, Futae no Kiwami (the "Double Layer Limit")—he can drive a blade into the ground to strike from distance, but mostly he just uses his fists.
When he encounters Sanosuke in a forest, he teaches him this secret technique, not knowing Sanosuke is working with Kenshin. That becomes his undoing. Sanosuke defeats him by evolving the Double Layer Limit into a Triple Layer Limit, striking with his knuckles, then his fist, then his fingertips in sequence. In that moment of defeat, Sanosuke makes him realize the life he's been living—the violence, the revenge—isn't what those dead children would have wanted for him. As he falls, Anji actually sees their spirits. After Shishio's death, he accepts 25 years in prison in Hokkaido.
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