I work with this guy. I know, bad idea. He's 29 & im 20. Which honestly I dot see an issue with the age gap. Anyway, we've hung out outside of work, just the two of us. At one point conversation got heavy and the intention was sexual. On a few occasions he's given me this, were just friends speech because our coworkers have caught wind of things a few times. But I'm so confused by this. He always says we're just friends and then we fall back into this sexual flirty tension. Also want to add we haven't slept together but if things keep going this way I see it happening... I'm not necessarily looking at a relationship unless we come to an agreement we want that, which is unlikely unless one of us got a new job. 

What would you do in this situation?