For more than three years now I have lived with Laurie who is nine years younger than me. Her aunt died back then and left her house to Laurie, so financially it has been great although I do pay all the utility bills and can still afford for us to go on trips often. I'm an independent trouble shooter for my company and work crazy hours, sometimes day but often at night. At night and ofen a day or two goes buy without me working. Laurie has a good job at a real estate office and also works crazy hours at times so there are days I don't even see her. We were ony living here a few months when her sister Annie moved in with us because she was having problems with her parents. She is only 23 now and every bit as attractive as Laurie. She is a waitress at a bar/restaurant and works 4 or 5 nights a week so I am at home with her often during the day. It only happens when Laurie is at work and I still haven't figured out whether Annie is just stupid, on drugs or if she is an exhibitionist. As long as Laurie is out Annie has no modesty around me and I often see her completely naked. Even when Laurie is home Annie still wears flimsy outfits but at least has her body covered. I never mention any of this to Laurie mainly because I not only like seeing Annie like I do but it also turns me on so much I frequently masturbate because of it. She has a great body, she knows it and basically flaunts it around me. She roams the house often with only a towel around her and if she does have any type of robe on its never fully closed. She thinks nothing of going around in her bra and panties and many times as she leaves the bathroom after a shower walks down the hallway naked but only when Laurie is out of the house. Not to often but I have also watched her masturbating with a vibrator many times over the last few years. I am sure she purposely leaves her bedroom door open a few inches knowing I am upstairs and can hear the buzz from the vibrator. When I do hear it I go over to her door and watch getting a hard on right away and then have to masturbate myself. I wasn't to keen on having Annie move in but I sure am glad she did.