What grade is he in. If you have friends in higher grades then him, tell him they if he wants to fuck with you then he has to fuck with all of your friends. That's what I say to people and that back the fuck down, or they get their ass completely trashed by me or some of my friends and I jump them. A couple people that we did that to ended up in the hospital for a couple of days or even longer. But if it comes down to them fucking with your friendship, espesially if it's a friend that's a girl, then I would just beat the livin shit out of that motha fuckin sack lickin son of a bitch from hell. In other words hit him so hard that he goes back into his mother's womb, and doesn't ever want to come back out ever again. Goodluck