IENF-161 - My nagging sister, who always treated me like a kid, barged into the shower naked to wash my junk!

My sister always treats me like a child, constantly barging into my room. One day, she catches me finishing my shower too quickly and drags me back inside, complaining that I don't know how to wash properly. But she's completely naked, and as she starts scrubbing my privates, her expression shifts from annoyance to pure lust.