This has happened to me once before and now it's almost going there. Going into "the love zone". Currently, I've hooked up with this girl a couple of times. We started out just sex buddies. But now it seems the more we talk, the more she's starting to like me and the sex part is slowly drifting away.

The reason I don't want this happening is 1. I don't plan to go there, and 2. the last time this happened it completely bombed on me. The girl started liking me and I let it happen thinking it would benefit me. But the sex part completely went away and it became apparent that she wanted a relationship and put the sex on hold. And like that it ended. I don't want that to happen this time because I want it to stay strictly at sex.

How do I avoid this?

see her less often and manage her expectations

Think yourself lucky you can get anything from any girl mate, some of us get nothing.