Kasugai-kun wa, Mousou JK to XX Shitai

"I'll do whatever you want, Mikami."

Kiri Mikami is a high school girl who's known as "little miss perfect" by everyone else at school. However, she actually has an obsession with innocent and inexperienced boys. She really is a normal (?) high school girl, even if she fantasizes about shy boys!

One day, Kasugai, the biggest playboy in school, directly asks Kiri out. Although uninterested, Kiri is very interested in Kasugai's stories of his first dating experiences. In exchange for hearing his stories... she has to kiss him. From that day on, the two of them begin a less-than-innocent relationship trying to recreate the scenarios from the books she reads about shy boys...?

(Source: Manga Plaza)