Should i fight a bully?

i hate fighting, if it were up to me i would never fight, but lately a boy much bigger than my friend has been picking on him, he has told the teachers at our school an no one has done anything, he also told his parents and the boys parents, but it was dismissed as friendly hazing, the thing is the boy make sure to stay away from me and doesn't bother when i'm around, but i can't be around all the time so i was thinking if i give him a gentle beating and tell him to stay away then it might stop him bullying my friend, should i? i can't bare having a friend scared to walk to school and back