Millie wants me to pull her out

I keep pushing my dick into Millie's ass until I feel that my balls are completely empty. Millie is whimpering a bit, but she has felt me cum in her ass, so she knows that her ordeal is nearly over now.

I keep slowly sliding my dick in and out of Millie's ass, enjoying the pleasure that I feel from her sphincter squeezing my dick, but slowly my dick starts to go soft, and eventually Millie is successful with her efforts to clench her sphincter shut and my dick falls out of her ass. I hear Millie breathe out and see her body relax, now that finally my dick is out of her ass.

"Matt, I cannot believe you just did that." Millie whispers.

I don't respond, I just stand there watching her naked ass.

"Matt, you have had your fun, now pull me out of here." Millie whispers a bit louder.

I am thinking about what to do next.