I sit on Frank's lap.

"May I join you?" I slip up and over the arm of Frank's chair and into his lap.

"Uh, hello..." Frank looks awkwardly over at you.

"You know my sister..." You hardly seem happy enough to see me... Frank seems to be having a fairly positive reaction beneath me, though!

"Gimme that..." I pout. Frank is Sonic, and I handily super smash you off, ending the round. "Ha!" I stick my tongue out at you, wiggling into Frank's lap to let his cock straighten out beneath me.

"You're going down, sis!" You quickly pull up another round. I get zero suit Samus this time.

Frank's hand somehow finds its way into my shirt before the round even starts, fingers sliding up my side, dangerously close to discovering my lack of bra, and I lean back to whisper: "I'm not wearing panties, either..."

By the time I've got you to 30%, one hand is cupping my breast, fingers teasing at my nipple, and the other is conspicuously slid up my thigh, my loose skirt presenting no obstacle as he makes first contact with my smooth-shaven little lips.

I attempt a tentative super smash to no effect, leaning back to whisper once more: "Take something off me..."

"What, um, should I..." Frank starts, and I glance at you, still engrossed in losing to me, and frown.

"Whichever. Both. Just do it." Another super smash. You utterly fail to recover, falling off the bottom of the level.

"Fuck!" You shout, not even noticing as Frank pulls my shirt up over my head, my bare breasts in plain view. My skirt gets roughly yanked down my legs seconds later.

You drop down from the respawn and I'm prepared. You're at 40% before you ever touch the ground, still grossly unaware of my nudity. Zero suit Samus rocks!

Frank's cock found it's way out at some point, and is nestling it's tip in a place firmly reserved for yours. Time to get some attention. "So, Frank, you think I can still whoop my dumb big brother's ass at Smash Brothers with a mouth full of your cock?"