After vanquishing a demon king, saving mum, and reconnecting with her friend Danny, Momo ought to be living the life she's always wanted. But lately Danny has been ditching her to hang out with mean-girl Ryleigh. When a whole group from Ryleigh's exclusive birthday party disappears, Momo and her friends (including Niko the fox) are left to fight a dangerous new enemy from Shintò„ legend. They're up against Tamamo-no-mae - she's the ultimate mean girl of the Kami-verse. To defeat her, Momo must travel to the Sky Kingdom and steal the legendary Mirror of the Sun. But if she's going to survive monster ambushes, escape giant snakes, and pull off the heist of the millennium, Momo will have to find a way to work with her team (even Ryleigh), and grapple with the growing power that connects her with her storm god grandfather and her greatest foe - Izanami the Destroyer.