From J-Novel Club:
Deep in the unexplored reaches of the dungeon, a corpse is discovered. One that shouldn’t exist. After Iarumas is resurrected, his memories of life before death are gone, and he spends his days delving into the dungeon to retrieve the bodies of dead adventurers. Can they be revived as well? Or will God reduce them to piles of ash on the altar? Either way, Iarumas collects his finder’s fee. And though his skills earn him some grudging respect, he’s also scorned for this cold, utilitarian attitude. The living keep their distance. Iarumas consorts primarily with the dead. That is until he meets Garbage, a feral young swordswoman who’s the sole survivor of a massacred party. With Garbage by his side, Iarumas ventures deeper, scouring the dungeon for clues to his past, avoiding monsters, traps, and the inevitability of a permanent ashen demise.

Set in the role-playing world of Wizardry.