Arisa lives with her husband and son. Her husband is a perverted man who flirts with her even though they have a son who is a student, and the son is fed up with seeing this. One day, the son sees his parents having sex and his desires explode. The next day, the son tells his mother, "I can't take it anymore!" and he forces her down and rapes her. Arisa reluctantly accepts it at the time, but gradually different feelings begin to grow...