Teenage math whiz Kenji Koiso agrees to take a summer job at the Nagano hometown of his crush, Natsuki. When he arrives, he finds that her family have reunited to celebrate the 90th birthday of their matriarch. His job: pretend to be Natsuki's fiancé. Meanwhile, his attempt to solve a mathematical equation causes a parallel world's collision with Earth.

Cast:Ryunosuke Kamiki, Hitomi Miyauchi, Mitsuki Tanimura, Sumiko Fuji, Ayumu Saito, Takahiro Yokokawa,

Genre:Animation, Science Fiction,

country:Japan,

Production:Madhouse, Nippon Television Network Corporation, KADOKAWA Shoten, D.N. Dream Partners, Warner Bros. Japan, Yomiuri Telecasting Corporation, VAP, Studio Chizu,