After being reincarnated into a fantasy world overflowing with cheat abilities, the middle‑aged hero Hoshino Jurota, nicknamed Juro, easily defeated the Demon King. His victory won him fame as the strongest, but soon after he realized his level was slowly and inexorably dropping. Desperate to survive in a world where his former strength was fading, he tried to curry favor with the royal family. Instead, he was placed under constant surveillance by the beautiful Princess Stella, who became his “fake wife” and forced him into a cohabitation arrangement. Now Juro must bluff his way through daily life under the same roof as the princess, hiding his progressive weakening while navigating a chaotic household comedy. The narrative follows the tension between his declining power and his need to maintain a confident front, the misunderstandings and growing closeness with Stella, and the broader question of whether a fake marriage can turn into something real.