

I know this late but here's the sauce
http://www.mangago.zone/read-manga/ai_to_yokubou_wa_gakuen_de/

Wait what does knotting mean??

If Dojin is so turned on, it's like, the head of his dick swells up inside and it kinda locks them together (knot). And if he tries to take it out then it would hurt hyesung. So they would need to wait for it to go back to its original form so he can take it out. Im not good at explaining, sorry... kekeke
Not hating but all the girls are super annoying and half of the time the MC always get hit for no reason.