How to I get someone to leave me alone?

I am 14 and in 8th grade and one guy wont ever leave me alone. All last year he made 7th grade SUCK and its only going to be the fourth day tomorrow but I cant take it anymore. I may have knew spot to sit at lunch during lunch he always talks about stuff like and how he make me and my Friend try to feel bad all the time. My locker is right next to his, he is in my homeroom, he is in my Industrial tech, study hall and gym he is just a big F****ing A**hole he trys to make every one feel bad and no I'm not going to help him he is making me go crazy if I really tell him off he will probably spread rumors about me and its middle school which means everyone will believe him all us middle schoolers are dumb about that stuff please help I cant take it.