How do you deal with an annoying brother?

my brother is 2 years older than me and very annoying. I just cant deal with him anymore. He is driving me crazy. I know people have said he'll grow up and you'll become best friends, but he's 15, in one month he'll be 16, when is he going to grow up? He uses things as a reward or punishment. I like to watch buffy, we own the dvd's, technically there his. If I cant help him with something then he'll take them away from me. My parents never punish him. He never seems to get that he is hurting me. He does stuff he knows will hurt me the most. He will always taunt me about hockey or baseball games that i have lost. He also calls me fat and a hippo, i have worked hard to become a healthy weight and I am sensitive about that, it is very hard to hear him say that stuff without wanting to pig out on chocolate. Please help!