The Unwanted Undead Adventurer

Rentt Faina, a 25-year-old adventurer, has spent the last decade fighting monsters, though he's never been particularly skilled at it. His typical job consists of hunting slimes and goblins for minimal pay, a routine that's left him feeling stuck. While exploring the Water Moon Dungeon, Rentt stumbles upon an uncharted path, which leads to an unexpected encounter with a legendary dragon. The dragon swallows him whole, but Rentt's fate is not sealed; he awakens as a skeleton, his body reduced to a pile of bones. With his trusty sword and tool belt still by his side, Rentt sets out to achieve Existential Evolution, a goal that might allow him to regain his human form and return to civilization.