The protagonist, Yanlian, returns to the street where he used to live, Kamigahara, and feels a sense of disharmony. He should have lived on this street, but he has no memory of what happened back then. At this time, a game he has never seen before, called "Monster Strike", is suddenly installed on Lian's smartphone. He takes the monsters that fly from the phone to the real world and starts a battle on the street! After the battle, Lian noticed the true identity of the mysterious memory sleeping in his body, and what Monster Strike is. Together with Mizusawa Aoi, Shadow Moon Akira, and Wakaba Kaimi who hold the key, Lian is now taking a step towards the mystery, and still knows nothing about the unimaginable truth sleeping ahead.