When you get this line, the great majority of time, she's being pretty forward in letting you know you can have her. There's no incentive for her to ask you a question like this unless she wants something from you (your penis). As you know most women will stay the hell away from guys if they have the option - they really only want to engage and WILL OPEN the guys they like.
This is one of the lines i've always heard about through the years but truthfully I was only the recipient of it once. It was at an edm event at a club, this woman brushed up against me and asked if she knew me from this club / if I had been there before. I always thought it was bs but she very well could have seen me there because we both would go there semi-regularly.
I always got opened in different ways / with different lines other than the above.
Rarely get this in all honesty....
It's probably happened many times but a lot of times you didn't notice because it was innocuous - it's almost never something so blatant from just the words that you think "she just straight up told me she wants me to beat her guts in". There's always an element of plausible deniability I think the phrase is. Recently I made a post about a walk I took - I came across this couple in my neighborhood that were chatting. As I got closer I noticed the woman started looking at me, back to the guy, me again and so on. As I was about to pass she turned away from the guy mid sentence to face me, squared up and she told me liked my t shirt. I was wearing some plain red coca cola graphic tshirt I got from like Target, nothing special about it. I just said thanks and kept walking but I could tell she wanted to chat and I could have very easily taken it further. About a month and half ago I was at this place here called Sugar with a friend of mine. These groups of girls came in, they sat next to us and after like a minute or two the woman who sat besides me turned to me and asked me what I was drinking, that it looked good and she would maybe try one. Before asking her name, I told her she could try some of mine and then I began to put the moves on her and got the number when I left.
The above is not meant to be humble brag, just examples of things to look out for out in the wild. The point is whenever you are opened by a woman there is a good chance you are in --- they are not going to blatantly tell you that tho.