This is downright hurtful.  So, a person may not have what some would consider the "ideal" looks.  This does not give anyone the license to make fun of the person.  People can't help the way God created them.  Try looking at the heart; that's what truly counts when it comes to true beauty.

Real beauty is in on the inside. Inner beauty is only the truest sense of beauty. Appearance does not matter when you need a friend.

I reckon that making fun of your friend's looks, especially if they don't want to hear about their looks, is a big turn-off. My friends have tried to make fun of my looks and it turned me off. If you do this too often, chances are your friends will abandon you.