What do I do now?

Welcome to the world of immature boys. If I were you, I wouldn't waste one more thought, tear, or breath on him. If you didn't do anything with him(meaning sex or sexual actions) he's probably pissed because that's all he wanted from you. He doesn't want his friends to see how great you are so he's painting an ugly picture of you so they don't try to go for you. He's being a jerk and the best thing to do is ignore him. Keep your head up, don't show that it bothers you, and get over him. He's not even worthy of your friendship for acting the way he is.

Let him do what he wants, just go and do your own thing, it only hurts more if you dwell on it. By making a fuss about it, you'll only be making it worse too, so just take a deep breath, and live YOUR life, not his.

My advice is to stay away from him, not for him, but for you.

How can you be friends with someone who disrespected you like that? The simple fact that he degrades you to all of his friends doens't bother you?

I think friendship is built on respect and equality, both of which you don't have.

Hey.
this happened to me and my ex and we stopped talking completely after. He blamed me for breaking up him and this hoe (which I didn't do) and then he started saying shit about me. So don't let it get to you. If everything works out. Later down the road he will talk to you. Right now he is talking to me but we aren't the BEST of friends but I think everything will work out.
good luck