Angryverse/Sally

Sally is a character created by Castanova who attends at Romance High School, where she's trying to impress Cathy's boyfriend Jim. During her spare time, she also is the official captain of their football team, under the guise Gregor.

Cathy also has a crush on "Gregor". I guess they're now friends with benefits.

Angry Birds Comics
Monsters and Mistletoe - The Journal