Should I ask this girl out? My sister says she is trailer trash but I like her a lot...?

I just bought a condo and one of my neighbors has really shown an interest in me and I really like her too...problem is one day when my sister stopped by I was outside talking to this girl and my sister saw her. She happened to be outside smoking and I was talking to her She had on a pair of shorts almost up to her cheeks and you could see her lower back tattoo...When my sister and I went inside, she said who is that girl you were talking to...she looks like trailer trash...I asked her why and she said the only girls who dress like that and have tramp stamps a s l u t s and the only girls who smoke virginia slims are loe women...now I have always secretly admired women who smoke, have tasteful tattoos and can pull off wearingh shorts like that..I want to ask her out cuz i think she is hot, but am afraid to tell my sister i like her..she will know I am into that kind of woman and i am quite opposite..what should I do..I hate to p this up...i think she is really smart, hot,, and y at the same time.