I'm from a father-son household and have an older beautiful sister. One time, she caught me masturbating! 'It's okay, don't be embarrassed,' she said, and actually helped me with it. Eventually, I wanted to have sex and asked her, but she said, 'Hold back with your mouth. In return, you can move however you like.' So, I inserted my penis into my sister's mouth and thrusted quickly like we were having sex! My sister seemed very excited, making a blissful expression as she said, 'Let's do something even dirtier'...
