With thoughts of Alex's ass in my head and cock now fully exposed I was jerking off and getting very close to cumming. My sister said a few more things one of which caused me to shoot cum all over my stomach. She leaned a little close to me on the bed and it felt like her mouth was right near my ear. She whispered, "You must have loved sticking your finger into her tight little asshole." As soon as I heard those words my cock jerked and cum started shooting out all over my stomach.

I lay motionless for a little then my sister jokingly suggested that I go...