S05E23 - Buffy's Fair Lady
Synopsis
Buffy meets a chubby girl named Angela who has a crush on Jody. Buffy tries her best to turn Angela into a lovely young lady and puts together a party so Angela can make friends. Buffy gets Jody to dance with Angela, but he bribes another boy to dance with her. Angela is disheartened when she finds out that this whole party was staged. Buffy and Jody then apologize for the way they treated her and gets her to make friends the right way.