Start the fun.

Getting around behind her again you bring your hand down on her nice round ass with a sharp crack.

"Owwww!" she cries in surprise and jumps a little forwards.

"Stay still Bitch!" you order sternly "If you want my hot young cock inside you then you'll shut up, do as you're told, and take whatever I dish out."

You see her stiffen slightly but then she drops her head.

"Okay, I'll do anything just fuck me hard."

You crack her across the butt again, enjoying her yelp. This time she stays still though.

"Oh I'll fuck you very hard bitch. When I'm good and ready. First though we're gonna have some fun. Get down on your hands and knees. It's time to prove you'll do anything to get my cock inside you."