A man who runs a detective agency in Tokyo receives a request. It is from an apartment owner who says, "A female college student who is a tenant is being stalked, so I want you to investigate." The detective agency decides to install a hidden camera in her room. Later, what is captured on the camera is the apartment owner's young son coming to the female college student's room to play. The son pretends to be innocent and repeatedly does obscene things to her, such as squeezing her big breasts! In the end, the female college student and the young son end up having a physical relationship...