Respectfully assert dominance over Stacy

You smile condescendingly, but also a bit flirtatiously at Stacy as you watch her grow bigger from her own orgasms, just like you've been doing.

Sophie: "Aw, look at you, you're growing bigger in more ways than one! Okay, here's the thing: I get that your job was stressful and you had to be rough on me to make your boss happy, but I'm still a bit resentful about it. So you get to almost catch up to me, but I'm still gonna be bigger, and I'm gonna decide what we do with ourselves for a while until I've gotten it all out of my system. Sound good?"

Stacy: "(Hngg... Fine. It's not like I could... polish the ol' pearl as often as you anyways. Also, what in the seven blazing Hells and their anuses, Sophie, how do you do that?? I've been watching, and feeling your orgasms for half an hour straight, and you just never run out of ammo. If I'd known you were a raving fucking nympho, I'd've been taking a hands-on-your-pants approach to your position years ago!)"

You sit down on the ground in a more relaxed position, now that you have something to do other than masturbate, namely, bonding with Stacy over your shared giantess-hood. You reach for your vagina, your fingers running over your slick folds.

Sophie: "I don't know, I guess I just assumed I had a weird mutation or something. It's not like there was any reason for me to go to a doctor to complain that I'm too sexually capable. Anyway, you've always been kinda hot, I guess, so I totally wouldn't have been above whoring myself out for a raise if that's what you're talking about."

Stacy: "(Guurl, we could've had it all. But nevermind that. Can you put your ginormous fat fucking fingers to good use and make me cum?)"

Sophie: "Eh, it's pretty hard to hear you when you're this small, so I guess I do want you a little bigger. Let me know if I'm being too rough!"

You reach down and gently press your fingertip against Stacy's crotch, letting her do most of the work to avoid crushing her. Stacy forcefully humps herself against your single finger, going against her body's self-preservation signals to orgasm what must be the seventh time within half an hour. Your indomitable giantessly presence urges her libido beyond its constraints.

Stacy orgasms with a primal scream, and grows again. Now you can finally hear her without having to squint your ears.

Stacy: "Gawd... I'm exhausted... Bluh..."