Spank until tender, then eat.

GF always asks me to gently smack it first. And when I start fucking her doggy she wants me to continue slapping her ass. I get into a pattern of thrusting and slapping to a cadence

I vote for both at the same time, for a really long time! What a delicious sight either way 🤤

Or maybe both simultaneously so you can feel the soft irresistible strokes of my tongue mingled with the firm uncompromising blows of the palm of my hand?