Originally Posted by Mydriasis

Yick, being honest is your best bet. Just be like "Hey I don't like you like that". He's gonna get upset but it's REALLY not your fault he sucks.

He sounds like he's got some issues. This is one of those times when drunken debotchary comes back to slap you in the face.

Or you could always lie, and be like "So I met the coolest guy ever" or something. Which is really childish but it's another option.