Recently, I got asked to prom by this guy, T. I said yes without really thinking about and regret it.

T and I aren't really friends, but he thinks we are. I suppose that's partially my fault because I was nice to him because he was so nervous around me (I'm normally quite a jerk.) I don't know him very well, and I have heard stories where he has been really creepy and harassed a girl he liked before. Even before I heard the stories, I was a little squicked out by the guy, and I didn't really know why.

Anyway, T is extremely socially awkward. I admire his bravery in asking me, but I am extremely uncomfortable around him. I am pretty sure he likes me, but I had to tell him that I didn't like him back so he wouldn't get his hopes up.

Things then became really, really awkward between us, and I told him that he could take someone else because things were awkward between us. Now, we've gotten into a fight, mostly because I lost my temper with him acting childish and I don't really know how I can be comfortable with him again. How can I conduct myself better with him so I don't hurt him too much? He really wants to go with me to prom.

Tell him 3 things, with no one else around.
There's a great girl out there for him, but it isn't you. You just don't feel any chemistry.
There's someone else you're secretly interested in (even if not true).
You can't hang out with him because he still thinks you two mean more to each other than you do.

You tell him you will go to the prom with him but you are only going because plans have already been made. Tell him he is free to dance with other girls if he wants, that you're not going as a couple, just going together. After the prom you're done.

It's going to be awkward...

You tell him you will go to the prom with him but you are only going because plans have already been made. Tell him he is free to dance with other girls if he wants, that you're not going as a couple, just going together. After the prom you're done.

Well, thanks for the advice everybody! I really appreciate it. However, I've decided not to go with him. He's getting creepy, and I feel really uncomfortable around him.

Well that's probably best.