On her 18th birthday, Ami Nonomura wants to meet her father and brother who live far away. While searching for her brother's house, she is attacked by a thief, but is helped by Hiroshi Tazaki. They fall in love but discover that they are siblings.
A young woman named Kazue runs over a naked girl on a mountain road. When she stops to help, the girl runs off into an old abandoned house in the middle of the woods.