School bully revenge

Lee Kyung Ho's mind was engulfed with ending his life due to bullying and the loss of his mother. He attempts to, but is saved. His determination to commit suicide somehow entices Sierra, a grim reaper who later offers him a contract. This contract blesses him with the ability to borrow the powers of the dead in their previous life in return of sacrificing years from his lifespan. For the sake of attaining what he wishes for, he eventually agrees to it.