Hey, I just wanted to say I loved every minute of it and that I would love to help you make games if you wanted any. I did find a small spelling mistake, you may wish to fix it. I woke her up and came on her belly after switching positions and this happened:
[Your sister] swats your hand away from your cock, and wraps her own hand around it and beings to stroke you.
The mistake is with "beings", it should be "begins"
I haven't published any games myself but I have some necessary skills, just FYI if you wanted to contact me.