Whats the difference?

If she tops, she wants to drill you. You take the female role and do the receiving. If she is catagorized as a "bottom", she wants your tool inside her. It can get all very confusing by some of the dubious ads by some of the girls. If,for example,all she has on her ad is "Bottom only", does it mean that she bottoms only,thus receiving, or that she will only accept bottoms as clients, those willing to receive her tool. All of it could get cleared up with just a couple more terms to clarify all the vagueness.