All the while, in spite of this being so wild and unusual and a leap into a taboo you're not ready for, sis talks to you like she usually does, teasing you, even if she's clearly nervous about this. "Tch...brat, trying to distract me...I'm still gonna win even if you're messing with...hah...me..."

Pulling down her zipper so slowly that she can't be sure you're really doing it on purpose, only when her girlcock springs free does she realize this is really happening. When your lips brush against the head of her cock, slowly taking her in your mouth, crossing a line you never thought you would.

Gaming with sis on the couch, resting your head on her lap as she plays some game she's obsessed with but you don't really care about...you feel her getting hard, and you don't know if you should say something, if you should move...but you know you really want to suck it...