Amane Todoroki is a girl who possesses ISH, the ability to use certain supernatural powers. Whilst her own power is fairly weak, she is able to borrow power from Lilianne, her twin sister who was born without a body and now resides in a stuffed bear. Amane has been doing magic shows with a few other ISH users for a performance group called Nought, which has been declining in popularity. One day, Amane is approached by an ISH user named Aya, who comes from another performance group called IAM.
Upon having her ISH abilities analysed, Amane is warned that if she and Lilianne were to keep fusing, Lilianne would disappear. Later, Amane and Lilianne encounter Aya and attempt to get her to change her ways, with no luck. The next day, Aya appears again and attacks Amane with an illusionary monster during a show. With Amane powers alone not enough to win against Aya, Lilianne suggests they should fuse, assuring Amane she will undo the fusion before she disappears.