Tatsuhiko Kido, a vocational/technical school student who's staying in his school's dorms, one day discovers a hole in the wall of his apartment room. He peeks through the hole, but when he does so, he sees his neighbor, Ikuno Emiru, masturbating and he's caught peeking! However, when he goes over to inform her of the hole in the wall, she shuts the door in his face. Luckily for him, he's able to stop the door from closing and pursues after her, but, in his haste, he trips and lands right on top of her. As luck would have it, she takes a picture of them in a compromising position and tries to blackmail him into getting naked?!

(Source: MangaHelpers)