Ever since you came home for the Holidays, your sister has been a total weirdo. She's constantly batting her eyelashes and licking her lips at you. What's even more strange is the fact that, the first night you were home, she leaned towards you as she was passing you in the kitchen and said, "ever heard of free-use?" and then winked at you! Of course, you've heard of free use; some of the guys at work talk about how their wives and even their in-laws are free use, but to hear it from your sister's mouth? It was all too much. You shrug it off but it gets to you. Later, upstairs in the bathroom that adjoins you and your sister's bedrooms, you can't help but stroke your cock to the idea of your sister's hot, wet mouth around your cock. A free use face fucking. You think you hear rustling and jostling on the other side of the door, but you ignore it, cumming hard at the thought of your sister's slutty mouth open wide for your fat cock. Of course, in the morning, your sister has something to say about it all. You hoped she'd ignore it but she's right there, first thing in the morning, and she's annoyed at you! "I told you I was free use, and then you go and masturbate? When I'm right there, free for a full, hard face fucking?!" it's like she read your mind. And the things she's doing with her body in front of you, the things she's saying...you can't believe it! If she's not careful, your mother is going to come in and see how she's behaving...which of course, only excites you more. She can tell your cock is hard from what she's saying and she smirks, motioning towards it, licking her fingers, playing with her long, wet tongue, showing you the depths of her pretty and willing mouth. She teases your straining dick with her talented mouth, showing you the soft and eager attributes that could be all yours, if you just say the word!