There was a girl whose mom told her that if she had sex before marriage she would turn into a horse or something like that. There's a guy in the girls school that everyone is afraid of because he looks scary but he's actually a normal guy. He gets a crush on the girl and she's afraid of him because of his reputation of being scary. He tries to talk to her but she thinks he's trying to have sex with her so every time they meet she ends up doing borderline lewd things to him to prevent actual sex from taking place. I don't think it was hentai just extremely ecchi

Bousou Shojo?

~4400 manga completed
~1700 ongoing...

Yes! Thank you! I knew shoujo was in the title yet I still couldn't find it.