My step-sister, Melanie Caceres, walks in on me stroking my cock, thinking I'm alone in the house. Her eyes widen as she takes in my exposed, throbbing member. Instead of leaving, she leans against the doorway, her full, curvy body accentuated by her tight, low-cut dress. "What are you doing, little brother?" she teases, her brown eyes sparkling with mischief. I freeze, my hand still on my dick, as she saunters closer, her huge ass swaying hypnotically. "You shouldn't be doing that here," she whispers, her voice sultry and commanding. But she doesn't move away. Instead, she leans in, her perfect tits inches from my face, and asks, "Can I help you with that?"