Theres nothing wrong with just wanting to hook up, as long as all parties involved are on the same page. To make clear that a sexual interaction is just a casual thing and not intended to DTR, be upfront from the beginning that thats what youre looking for. And once you do, you can enjoy the hookup!

What to say when you just want to hook up?

Try something along the lines of: “Ive been having a lot of fun and Im just wondering what youre looking for out of this.” Let her know that you dont need an answer immediately, but that youd like to talk about it before this goes too far.