Small stepsister pleasures herself with my huge manhood

I've got a bit of a conundrum on my hands. See, my stepsister's been acting quite strange lately, always finding excuses to come over and "help" me with various chores. At first, I didn't think much of it, but then I started to notice some suspicious behavior. She'd always be around when I was getting ready to shower, and then she'd suddenly remember she'd forgotten something and rush in just as I was about to step in. The other day, I finally caught her sneaking around my room, going through my drawers and stuff. I confronted her about it, and she admitted that she was just really horny. Apparently, she's been fantasizing about me for a while now, and seeing my huge manhood just did the trick. Surprised? I wasn't. After all, I've seen a lot of weird shit in my line of work. But hey, if she's into it, why not?.