Don't hesitate

You can't keep it up much longer and start pounding her for all she's worth. You know that you are infliction a good deal of pain on her, but her orgasm is slowly receding and she is still really into it, so you shove the slight guilt of hurting her mercilessly to the back of your mind and pour out a surprisingly generous stream of sperm down the depths of her ass.

You both collapse on the floor in a heap of sweaty tangled limbs, both gasping for breath. You slowly slide out of her tight, spasming asshole; leaving it gaping wide. Her crotch is pressed against the puddle of drying cum that dribbled out of her cunt as she slowly farts your last load. You get up and clean up a bit. That first real assfucking left your cock ever so slightly dirtied, but it was worth it.