Gakuen B

Aina ends up being late for school one day because she was having sex with her boyfriend, Fujioka. As punishment, the student council president, Nojima, tasks her with cleaning duty. Aina is cleaning out the equipment room when Fujioka sneaks up behind her. Thinking that they'll get a chance to resume their morning activities, they hear a sound outside and have to hide...

(Source: BakaBT)