"I want you to suck me off"

I reply, and move my cock towards Millie's face.

Millie starts to laugh, and says:

"Now, why would I want to do that?"

"Well, you know, return the favour so to speak?" I reply.

Millie climbs out of my bed and starts putting her clothes back on, and says:

"Sorry Matt, but I came with you since you offered to lick my pussy for me."

She continues getting dressed, then adds:

"Besides, I sucked you off last time and you did not reciprocate, so I feel we are even."

I stand there and stare at her in complete surprise, my cock still in my hand, then she picks up her bag and walks out the door, shouting "bye" as she leaves.