Hey, guess what. You don't know my friend, at all. Don't judge her by her physical appearance. Okay, so she's slightly overweight. Sorry, but last time I checked, you were at least seventy-three pounds heavier than her. Don't call her "fat" when, let's admit, that's what you are. And it looks like you're a pretty ugly person inside.

I don't mean to be discriminating, but it just sets me off when I see people criticizing my friend (who's very nice and never has said a bad word to anyone) just because of her outside appearance. 

It's probably not very fun to have people tell each other about how fat you are, and ask you out only to say "Nah, you're too fat. That was just a bet." Just... learn to be a real person and stop trying to torture people. You don't achieve anything by what you're doing.