Ashin has trained her entire life to be the ultimate weapon for her handler, Erebus, the God of Darkness, in his battle to be the only deity. She is, foremost, an assassin. Then she discovers she was created by Athena as a warrior, and is the Keeper of Wrath, one of the seven deadly sins. The war, she discovers is not about gods vying for power, but rather one for freewill. Ashin hopes to triumph before she loses her own freewill-permanently.