Coming home from work and hearing some clamoring coming from your bedroom. Opening the door you find your shy little subby size shifter isn't so little. She must have gotten really aroused either in her sleep or while browsing the web. Your thoughts are being drowned out by the massive moans that are escaping her lips as she humps your bed, covering a third of it in her needy juices. You know that at her current size she doesn't have the range of motion to get herself off or use any of her toys. You quickly grab her favorite wand and force yourself between her thighs and the mattress. Only then does her trance break and she notices you. "Sorry sorry sorry!" She apologizes profusely between moans. You aren't mad. She can't help it. You click the toy to life and press it to her swollen clit, eliciting another, louder, set of moans and triggering another growth spurt. She was already aroused to such a degree that all she needed was your helping hand before you feel her start to convulse as she begins to gush all over you. You barely manage to squeeze out from under her while she collapses on the bed, a whimpering panting mess.
Not wanting to miss this chance, you climb your towering girl and proceed to mount her. Her arousal begins to pick back up as you thrust in and out of her. Even at her enlarged size, she feels nice and tight after having just climaxed hard. It doesn't take long before she's cresting again as you finish inside her. With that, she begins to diminish, all her sexual frustration forced out of her by your caring hands.
You stand in awe of your lover, still well above average size as she continues to shrink down in her sleep. You patiently wait for her to get small enough for you to crawl into bed and snuggle her. A big smile crossing her face as you take her into your arms.