'Unleash the beast'

After a moment of hesitation, you quietly ask a question you already know the answer to. "Is that uncomfortable...?"

Looking embarrassed, Arya manages a quick nod, the anaconda in her shorts still throbbing as if **** to be set free. Even with that though, your generally well-behaved sister doesn't seem willing to just pull her cock out unasked; it's your job as the elder sibling to help her out, you suppose.

"Want me to...?" You don't get the whole sentence out, but with your hands tentatively reaching towards Arya's groin, she gets the idea. Another embarrassed, but almost immediate nod ensues, and your hands shake a little with excitement as you undo her shorts and slide them down out of the way. Beneath, you find a woefully under-equipped pair of panties, straining desperately to contain Arya's enormous cock...

You struggle to pull Arya's panties free as she lets out something between a whimper and a moan; the feeling of your hands messing about all around her turgid cock is apparently getting her even more worked up. Thankfully, you manage to pull Arya's panties down around her member after not too much longer...though they look like they'll be permanently stretched at this point.

The monster springs free, pushing up against your bulge immediately and ending up sliding up along your stomach. You can't bring yourself to look away from it...even if you've seen the like in porn, seeing it in person is completely different...completely mesmerizing. Your trance is broken after several moments by Arya's voice asking you a question.

You completely missed what she said, but it's obvious enough by the context and her body language that she's asking if you want her to get your cock out too.