GDHH-086 - My Step-sister is a total slut, but she loses her mind when she sees my massive size

My dad remarried and brought home a step-sister who's a total nympho. When she finds out I'm a virgin, she tries to tease me by pulling down my pants, but once she sees my massive size, she completely loses it. She tries to resist because it's 'too big,' but we end up breaking our promise not to go all the way. One thing leads to another, and I end up finishing deep inside her.