Weak kneed as Katie felt she knew that she wouldn't be able to stop Tiff from having her way with her. She needed to get away before it was to late. Tiff was already bending forward to plant her lip's on Katie's and if licking her blood had made Katie weak then she didn't want to know what a kiss would be like. As good as that might feel. With her free hand, she balled it into a fist and with all her strength she punched the largest target on Tiff's body. Tiff's DD breasts shook from the force of the blow but that was nothing compared to the scream of pain that came from Tiff as she dropped to the ground faster then a crotch kicked high school student.
Katie wasn't going to wait around and hope the blow had knocked some sense into Tiff. Likely it had pissed the demon off. She needed to get away but where should she go? Her House? and how long would she be safe there till Tiff found her? Or maybe the basement to get that wish-ray so she could change Tiff back. If Katie could even figure out how the thing worked. Or maybe there was something else in the house that could change Katie from her demon form. She didn't have much time either as even at the bottom of the stairs, Katie could hear Tiff's wings snap outward and her cry of rage.
Now was the time to decide.