South Park - Season Twelve Episode Nine

Cartman's comment on breast cancer enrages Wendy. After failing to reason with him, Wendy challenges him to a fight. Fearing that he would lose the fight, Cartman attempts to reconcile with Wendy but to no avail, so he resorts to telling on her. Now that Wendy has promised her parents that she won't fight him, Cartman becomes even more brazen, ridiculing Wendy in front of the class. Encouraged by Principle Victoria, Wendy finally makes up her mind to teach Cartman a lesson. Knowing that the fight is inevitable, Cartman reluctantly engages Wendy  and is beated up badly.