Ok here's my thoughts and opinions.....
Why the hell is the author pointlessly killing characters? Like at least show a foreshadowing that a bunch of those beasts manage to find a way to get in the school gym, like there's no girls guarding or watching if some of the beasts are getting near/inside the school?!?!??!
Also like didn't the sensei already said that the school is the safest place cause it like covers their hormonal smell?!?!??!
@ramunegaming here's my thought about your comment: Yeah the MC is smart, but if we really think about it... The MC have a freaking screw loose in his head. Like seriously, he killed all the people that raped and murdered his crush . Yeah most people would also get mad, angry, and sad about that, but most will think of first is working with the police and getting the criminals into jail, and not freaking seeking revenge and murdering them by cutting out their genitals.
Yeah MC is smart, but he got a screw loose to not think logically about him giving his sperm.
Also about the females getting the sperm while he sleep..... the girls could have actually have done that if like they drugged him to sleep and extracted the sperm lol(school clinics should have at least those kind of medicines).