Damn, the MC needs some lessons in self defense.
Even if your bully is bigger and stronger than you, it's easy enough to throw someone to the ground if you know what you're doing. Once he's on the ground and you're on top of him with a hold of his arm or neck, there's really not much he can do to you. But there'll be plenty of stuff you can do to him.
(on a side note: a game where you get to turn the tables and start bullying the MC's bully, that'd be pretty awesome)
As an NTR story, this one's really not bad though. The scenes are erotic, and the buildup is pretty good.
And IMHO buildup is everything in an NTR story. Just like with yandere and horror. The scenes will just fall flat without it.
This game could still use a bit more content, but all the right stuff is there.