sugarratio

“I love that part so much!” I purred. “The way his knot pulls against my entrance as he's thrusting! Holding him inside so he can't pull away!” I shuddered with arousal, imagining just how I knew it felt as I watched it happening to my own mother instead. “You should play with your clitty, Mom,” I told her. “Brucie's way faster to cum than Daddy is—you probably won't be able to get off on the fucking alone, not unless you help yourself out. In fact...” I thought about it, then moved to act, resting my palm on her mound and using the tips of my fingers to tickle her clit. “Actually, never mind; I'll do it for you this time. You just concentrate on how good it all feels, and try to let yourself cum!”

idk if you've played chaos;head (or watched it, I never saw it so idk if it's in the anime) but it's set in the same world as steins;gate (which I've watched but never played) and things the eyes see but the brain doesn't process are a literal plot point, you could almost certainly make a fairly lore accurate manip with that if you like this world.

“Oh, take it you little whore!” she squealed, her hips jerking powerfully against my ass, the hot, molten flood of her seed making me gasp as I felt it shooting deeply up my ass! “Take it! Take my fucking cum!” Wave after wave she gave it to me, her huge, amazing cock pulsing and throbbing in time with the unbelievable pounding of her hips. Then suddenly she stopped, almost as if somebody had thrown her switch, buried to the hilt but completely immobile. She stayed there for a long, slow moment, eyes closed in rapture, barely even twitching but utterly lost to the ecstasy of her release. She pulled out slowly, leaving me strangely empty and wanting, supporting herself with her hand on my stomach as she tottered unsteadily around to my side in her heels. She bent low over top of me, her huge, amazing tits pressing warm and heavy against my chest.