The brother and sister decided to have a movie night. My parents were out of the house and we could talk about everything. The younger sister is still modest and inexperienced, she accidentally let it slip that she had never seen or touched a man's dick in her life. Her brother gladly took her words to action... He decided to show her what a horny dick is and teach her sis to fuck. The girl was so scared when he cum inside her and ran to the bathroom to pee and wash the cum off her pussy. After all, she was so scared her mom would find out!