Orphaned as a kid and raised by her grandfather, Tian Nana grew up kind and upbeat. Her odd neighbour Brother Gouli talks to himself and plays with a toy sword. He claims he’s defied Fate when he saves her. Now, Nana must inherit his sword and demon-slaying duties. Plagued by strange incidents, a stalking toy sword and the ability to sense evil, Nana embarks on her adventures of demon slaying.