Skinny Girls vs. Not-So Skinny Girls

Today i experienced something that I thought only happened in the movies. I was in my Physics class and in my table there's three girls and a boy. There's me, a skinny girl and a not so skinny girl. So we're all talking and everything is fine until I notice that the way the guy talk to the girls at my table is different. He makes fat jokes and plays around with the not so skinny girl like shes a guy and even whispers mean comments about her. Not only that but he even makes sure that the girl knows he whispers about her. On the other hand, he treats the skinny girl better and even flirts with her, and let me tell you, the not so skinny girl is WAAAYYY better looking than the skinny girl. Basically, the skinny girls with ALWAYS be treated better than the not so skinny girls just because of that, they're not skinny. To those not so skinny girls: dont mind people like and move on, they're not worth your time. (: