An adult reincarnates with full memory and refuses to be the genius wanderer, he wants to be cunning, calculating, happy. That shift from "strongest" to "smartest about what matters" is the entire show. Seika knows the trap of power and walks around it anyway, which sounds simple until you realize how rare that actually is in isekai. The writing wavers later and forgets what made him interesting, but those early episodes hit because they let a grown man choose a different life instead of repeating the same one with better stats.
Haruyoshi Kuga stands at the pinnacle of his world: an unrivaled exorcist whose mastery over spiritual arts has made him legendary. Yet strength alone hasn't brought contentment. When the Imperial Court orchestrates his downfall, Haruyoshi refuses to accept his fate as just another casualty of politics. Instead, he activates an experimental reincarnation technique of his own design, betting everything on a second chance. He awakens in a fantasy realm as Seika, a commoner with no memory of his former glory. But the skills that made him legendary remain intact, dormant and waiting. Armed with powerful exorcist knowledge and the ability to contract demons as allies, Seika navigates this new world with a crucial lesson learned: raw power means nothing without strategy. This time, he's determined to pursue genuine happiness rather than hollow achievement. What begins as a quiet escape becomes something far more complicated as Seika's true nature starts surfacing, entangling him in conflicts he hoped to leave behind.