From Cotonoi: Maks Takano and his three best friends of Re, Natsuma and May-students of the private academy for gifted children. Like all other students in this isolated and strongly protected school, they have never seen the outside world since they were brought to school at the age of three. When a new student is coming by Kiriko Chinac, Maki has a strange feeling that he met her before. Nevertheless, he seems to be the only person who can remember the girl. When he faces her discovery, Kirico reveals the incredible truth about his existence: the school in which they lived all this time, in fact, is an experimental object, and all pupils-guinea pigs, which are used for complex neurological experiments. Macs now have to decide: