The main character is a girl who entered an All-Boys Highschool by accident.

Robin : It's… a GIRL?!

Some of them stare in shock while others are hiding under their desks in fear.

Yuji : I'm scared. Is she going to be like my mom? Ryou : Shut up, you idiot!

Okay, most of the students here are weirdos who have never seen a girl in their life.

How are you supposed to survive in this school now?!

Kei : Sorry about them, lia. What class do you have now?