I can't

As I look in the mirror seeing my sister feeling her boobs I can't stop and my hands run down the flat stomach I now have and slip down the shorts of my nighty.

As my hands reach down expecting a boner I instead rub over a shaved already wet pussy, what let me moan out loud from the unexpected pleasure it gave me.

"oh shit" I scream out in the high voice of my sister what makes me even more aroused somehow.

I have to sit down on the bed again, but can't stop rubbing between my legs let my sisters voice moan as I use her slim fingers to start fingerein myself in her body.