Henri Cleats is a desperate young adventancer whose only skill is Evasion, an ability considered nearly worthless for combat and dungeon exploration. With his younger sister Colette suffering from an illness, Henri needs money for her care, but his low attack power and lack of useful skills lead to him being bullied and ultimately expelled from his party. Alone and with few options, Henri ventures into a dungeon by himself, where he accidentally discovers an extraordinary glitch: his Evasion skill allows him to pass through walls. This ability lets him bypass boss fights entirely and reach the treasure rooms of dungeons directly. Even more significantly, he finds that by using this wall-clipping bug, he can repeatedly claim the valuable First Clear bonus that is normally awarded only once per dungeon. Set in a fantasy world where adventurers rely on their unique skills to conquer dungeons, the story follows Henri as he exploits this loophole to accumulate rare items, boost his stats, and rise from the weakest of adventurers to unprecedented power, determined to secure a future for his sister. An anime television series adaptation has been announced.