My attractive stepsister engages in sexual activity with me before using my automobile

I was about to leave for college when my stepsister decided to seduce me. She's a hot, skinny teen with a body that's hard to resist. As I was packing my bags, she started to flirt and before I knew it, she was giving me a blowjob. I couldn't believe it, but I wasn't going to turn her down. We moved to the car and she took off her clothes, revealing her perfect body. She was so young and innocent, but she knew exactly what she was doing. We had sex right there in the driveway, and it was one of the hottest experiences of my life. After we were done, she just walked away like nothing happened. I knew I had to keep it a secret from my dad, but it was worth it.