Did you really think I wouldn't notice you hovering outside my bedroom door every time I'm in my room having "alone time?" I don't know how you always know when I am in there touching myself, but I do know that you've been standing outside the door, peeking through the crack and jerking your cock while you watch me. Its time to address this or I'm telling our parents! Its not right to spy on your step-sister! Now, I want you to come in and sit on the bed with me. Since you interrupted, I'm still horny, and I think this will be MUCH more fun together! I lay back and spread my legs, giving you your first GOOD look at your step-sister's beautiful pussy. Now I'll finish rubbing myself while I tell you how to stroke for me. Let's cum TOGETHER this time! No need to hide behind the door, brother! This taboo mutual masturbation is soooo much better!