Initially happy, then concerned.

"YANG!!!" Ruby cheered, dropping her weapon and diving for Yang, wrapping her up in a bear hug. She then blushed as she realized her face was nestled against the silk of Yang's boobs. Naughty thoughts threatened to resurface, and she quickly pulled back, trying to regain her composure. "Um... Are you okay?"

"I'm happy to see you too, Mistress!" Yang giggled, placing a hand on the wispy border of one of her "hips," jutting out out. "And I've never been better! You like the new look! Because I certainly love it!"

"Um... It's nice, if a bit... Provocative, even for you," Ruby said, cautious. "...wait, why are you calling me Mistress?"

"Because I'm a Sex Genie now, Mistress!" Yang replied brightly. "That means I am a **** to whoever holds, or at least last held my Lamp while I was summoned! I can't call you anything else without your permission!"

"Um, uh, okay, well, you have my permission to just call me by my name," Ruby responded awkwardly, her mind trying to process everything. Sex Genie? ****!?

"Okay then, Mistress!" Yang replied cheerfully.

"Um... You're still calling me Mistress?" Ruby questioned, confused.

"I'm sorry Mistress, was it an order to call you by name instead of your proper title?" Yang smirked. "I must have failed to mention that just because I no longer have to call you that, doesn't mean I don't want to..."

Ruby looked on the verge of tearing her hair out. "What the heck is wrong with you!?" she shrieked in a high pitched, panicked tone. "This isn't like you at all! Where the heck did my assertive, snarky sister go!?"

"...um... Right here, Mistress," Yang quipped, gesturing towards herself as she wiggled her "hips." "Granted, I have a new perspective, and after being bound to the lamp, I desire nothing more than to serve a Master or Mistress now."

"Um... Okay, but... Is there any way to undo this?" Ruby asked, and Yang pouted.

"Mistress, there are only two ways I could be freed," Yang replied, crossing her arms as her pout deepened. "The method I would prefer, and believe me, I would really prefer it, is to simply serve my "term." See, the lamp feeds on some kind of metaphysical energy produced by sexual satisfaction! Essentially, I would have to fulfill a large quota of sorts to satisfy it for a while, then it would cut me loose after I finished serving my Master or Mistress at the time of my quota being filled, and move on! That would take a couple centuries at least though, thank Oum," she sighed. "Though I won't age for the duration!"

Ruby stared at Yang. A couple of centuries as a ****!? And that was her preference!? "And the other method?"

"You could also wish me free now, but then it would need a substitute, and either take you or someone else if you had them to offer up... I'd really rather you didn't do that though! I don't want to give this up! I know I'll have to return to being human eventually, but this is too amazing to lose before that inevitable time!"

"Okay, seriously, are you just plain brainwashed?" Ruby demanded, putting her hands on her hips, struggling to wrap her head around the idea that Yang would actually want this.

"Not as much as you might think!" Yang winked, placing her hands behind her head casually. "There are some mental alterations that come with being a genie, but it's really just a little bit of "rewiring," so to speak. Basically, if I was already submissive, or a switch, it makes me enjoy obeying commands a lot more, I am capable of really getting off in it now! If I was dominant, then it would make me something of a switch! Still enjoying domination with everyone else, but wanting to submit to my owner specifically, and loving that more! It also grants me magic I can use for fun at your will! And it removes all of my inhibitions, and grants me every possible kink! The thought of obeying literally any command makes me feel so fulfilled now! But I AM still Yang, I promise you that! Every part of me that made me me is still a part of my being, it just takes a back seat when it comes to following your orders!"