The song is basically about a girl who wants a man that will treat her right. "Rub her the right way" means making the right impression. She feels the physical attraction to a man, but she doesn't want a relation that's purely physical. She wants a man that will care about her emotional and mental well-being as well; someone that will care about her as a person. She's saying that if they do that, then she'll be their girl and their's only.
The song is basically about a girl who wants a man that will treat her right. "Rub her the right way" means making the right impression. She feels the physical attraction to a man, but she doesn't want a relation that's purely physical. She wants a man that will care about her emotional and mental well-being as well; someone that will care about her as a person. She's saying that if they do that, then she'll be their girl and their's only.