This is a total betrayal and you tell her she will be kicked out the sorority. She says she’s sorry and pleads with you to no avail until she offers to take a spanking if she can stay in the sorority. Thinking it will be a nice revenge, you agree, and spank her over your knee and then finish up with a bunch of swats with the paddle on her bare bottom.
When you’ve finished, she collects herself and then informs you of the anti-hazing policy of the sorority, which forbids corporal punishment. She then threatens to kick you out of the sorority unless you take exactly the same spanking as she took!