Sanpeita Kobayashi's gorgeous buddy had to move away when he was a youngster, but she pledged that in 10 years, they would meet again—as husband and wife. Sanpeita is a high school student 10 years later, but he hasn't forgotten the sensations they had. Sanpeita awakens from a dream about his final day with her, only to have his day disturbed. In his bedroom, a strange robot female, claiming to be his wife, is battling other robots. The pilot of the robot resembles Sanpeita's long-lost childhood pal. But who exactly is she? Why was she forced to leave? And what is her connection to the Mishima Electronics Corporation?