My sister brought her boyfriend home and said, "Don't look in my room, okay?" and had sex with him in the room. She knew I was looking in and was licking her boyfriend's dick to provoke him. My sister was frustrated with her boyfriend's sudden ejaculation. I was left alone with my sister. While playing a game, I noticed her panties and got an erection. When my sister noticed my erection and started to make fun of me, I opened my legs and she got excited. Our sexual desires were unstoppable, so I put a vibrator in her and she peed herself. I made her take my erect cock deep in her throat, crossing the final line, putting my cock in her slit, and my sister was so excited that she couldn't stop peeing again.