Kanojo ga Boku no Shiranai Tokoro de

Hiroki is over the moon at getting a girlfriend, a girl named Hikaru. The two get up to naughty things in the nurse's office, and all seems well until Hikaru goes back to get her handkerchief. There she finds a guy already sitting there, Takumi, who shows her some interesting footage he just took… (Source: Fakku!)