MoonlightWyvern
When someone dies, they sometimes leave behind a shade, a being made of all of their regrets and past crimes. In order for them to move onto the afterlife, the shade needs to find peace and overcome their regret... but most cannot do it alone. That's where Reapers come in.
In the Maze, hundreds of shades are trapped, plagued by their regret and bad memories. When Apo meets his untimely "demise," he finds himself bound between life and death with a new task of helping the Outsiders find peace, whether they're dead or not.