Kim Jun-Woo, the world’s first SSS rank genius hunter.
He is an incredible user of ability, but his horrible personality leads to problems with his reputation.
In the midst of his troubles, he was attacked and killed by an unidentified group.
And when he opened his eyes, he had returned to the past of 10 years ago.

Though he tries to become a hunter again and raise his rank, his skills were all sealed by the karma of his previous life.
In order for that to be released, he needs to work as a ‘Dungeon Cleaner’, which is infamous for being extremely tough in this industry?!

But this cleaner, he’s different!
Not only monsters—troublesome hunters, superiors only taking up positions after they’re hired out of nepotism, and even people who will be colleagues with him.
He’s making a complete mess to clean everything up.
The ex-hunter, who is stronger than the current hunters, and his crazy cleaning begins!

세계 최초 SSS랭크 천재 헌터 김준우.
대단한 능력자지만, 인정머리가 없는 탓에 평판에 문제가 생긴다.
골머리를 썩히고 있는 와중, 정체를 알 수 없는 집단에게 습격받아 죽게 되고,
눈을 떠보니 10년 전 시점으로 회귀한 상태.

다시 헌터가 되어 랭크를 올리려 했지만, 이전 생의 업보로 인해 스킬을 모두 봉인 당하고,
해제를 위해서는 업계에선 극한 직업으로 유명한 '던전 청소부'로 일을 해야 하는데?!

하지만 이 청소부, 남다르다!
몬스터는 물론이거니와, 골깝떠는 헌터, 자리만 차지하는 낙하산 상사, 심지어 동료가 될 사람까지
모든 걸 청소할 기세로 깽판을 치는데...

현직 헌터보다 더 강한 전직 헌터의 망나니식 청소가 시작된다!