Search Results: hooking up with best friend

He is 27, I am 24. We have worked together for 3 years, plus 3 years of friendship in that time. Both Single.
He messages everyday (pictures of funny stuff or him just saying ah work was awful today. I am the only one at work he messages We hang outside of work a lot in groups, but i am the only one he hangs out with just me.

i have met all his friends and they like me and he pointed this out to me making a big deal that one particular friend normally does not like girls. They have also asked me about the idea of him and me together but I said no at the time. Even our boss and other staff have suggested.
he also seems to be a bit nosy which i take as a silent jealousy when I talk about other boys and when my ex comes into our work.

We both flirt a lot, I do not feel as if there is a friend zone on either side so there is room to move, however we are both too shy in the department to make a move.
He is seeing someone casually atm, he did not mention it re-started but he told another worker my close female friend, that it was nothing just fun. I also caught this girl hooking up with her now married ex the other night, and suggested the idea to my guy that she was shady which he took on board.

He has also been set up with my best friend, i realize i did this now subconsciously to try and not feel what i felt for him, as i have been in a work relationship before and it did not work. However she lives over seas now, and it was a one night thing [NO NOT ALL THE WAY] she even suggested me with him after this.
I am wondering how to play it now, is there a way I can test his friendship vs. his romantic tendencies for him. I can not ask a co-worker or his friends. If the answer is no, it would not be good for the friendship or work.