The Once-Unbeatable Hero: My Secret Level-Down Life with the Princess

Jūrōta Hoshino thought he'd hit the reincarnation jackpot. After being reborn in another world, the middle-aged man was blessed with an absurd assortment of cheat abilities. He became an overwhelmingly powerful Hero, defeated the Demon King with ease, and completed the sort of grand adventure most isekai protagonists can only dream of. Then his levels started going down. Apparently, once the Hero's job was finished, the extraordinary power granted to Jūrōta wasn't meant to last forever. Day by day, the once-invincible Hero is becoming weaker. For Jūrōta, this is terrifying. His reputation, status and very survival depend on everyone continuing to believe that he's the legendary Hero who defeated the Demon King. If the truth gets out, there's no telling what will happen once his former enemies realize the supposedly unstoppable Hero is rapidly becoming an ordinary middle-aged man. Desperate to secure his future while he still has some influence left, Jūrōta ingratiates himself with the royal family. The result isn't quite what he expected. The kingdom assigns the beautiful Princess Stella to keep an eye on him, and before Jūrōta knows it, the two are living together as a provisional married couple. Now Jūrōta has to maintain his dignity as the world's legendary Hero while desperately concealing his declining stats from the princess living under the same roof. And as goblin girls, orc girls, old enemies and new responsibilities begin intruding on their strange domestic arrangement, keeping his secret becomes increasingly difficult. Worse still, what began as a fake marriage may be developing into something neither Jūrōta nor Stella expected.

A fantasy romantic comedy about an overpowered reincarnated Hero whose adventure begins after defeating the Demon King, when his cheat powers start disappearing and he has to bluff his way through retirement without letting his beautiful fake wife discover that the world's strongest Hero is becoming weaker every day.