My sister just turned 21 and has a rough go of it the last few years. She had no place so I took her in if she would clean up her act and get a job. She has gotten pretty hot over the past few years. She is very tall slender with long dark hair and a nice set of tits. I have noticed the change in her very slowly over the past year or so. Anyway I have a big black pantyhose/stockings fetish and one day she came home from her new job and was wear a sexy knee length skirt with the black pantyhose and heels. I tried not to look at first and figured she would just go to her room and change to back out and talk to me. She didn't change and proceeded to sit down next to me in that outfit and talked about her new job. Well after about 5 minutes or so I started to stare at her outfit and started to get a massive erection. It got to the point were I actually concealed my phone so I could take a vid of her in this outfit. I excused myself so I could go masterbate I was so turned on by her. She will wear outfits similar to this once or twice a week. Everytime I see her in these outfits the samething happens. It become so bad at points like I will go threw are dirty laundry just to feel are black pantyhose. I don't know if it is because I haven't been laid in a long time or what but I have never had this happen to me before. I have considered asking her to leave because it has gotten so bad for me. I feel like a sick,twisted fuck but I have never had any thoughts of having sex with her or anything sexual in nature just love it when she wears those outfits. I just wanted to share that with anyone who cares.