Libra - venus in scorpio, mars in aquarius?

With all this water thrown in there I doubt he's detached and non-chalant about emotions, and Libras are the most relationship-oriented of the air signs (I am too, a Gemini).
How soon did you two got together after you met each other? Was it a quick hook-up? Men are different when it comes to jumping to relationships and committment, it has alot to do with how it started/who initiates etc...
Don't get into 'lets-have-a-talk' mode too soon, thats never a good way to get a man to open up...and it does come off as pursuing most of the times...
Take it slow, get to know each other and let him man up and do his part - there s no point running after him. Seeing he has moon and venus in water signs (which show the qualities/traits he falls for and feels comfortable with regarding to women), he probably appreciates closeness and emotional approach but to do that you have to tap into your feminine role and dont pressure him into commitment.
If he doesnt pick up the slack and distances himself furthermore, you got your answer: it IS a fling...

PS. of COURSE he's intense with venus in scorpio, merc in scorpio (the way he communicates/thinks)...and with moon in pisces he can be more open and capable of showing emotions...Mars in aquarius, yes, his style of pursuing might be peppered with aloofness, YET, dont forget its a masculine sign and aggressive nontheless

He s a man, still...so dont attribute everything to signs, bear this in mind as well...let him tap into his role...

Wonderful advice.. I know it's all true, and I am definitely not one for the 'lets have a talk' stance, but I do like to know where I stand. Usually I can get that from people straight away, most certainly Libra men but with this guy, .. it's a mystery. I think I should just see what happens. As much as it kills me.
We had known each other for a while, but I was always a bit withdrawn around him, as I tend to be on occasion (for a Gemini, I'm quite 'sullen' and moody sometimes, cancer rising?) but gradually I opened up and we clicked straight away. Lots to talk about, and he has a certain sexual magnetism I find very appealing. I did the initiating, but we didn't hook up immediately. Sat around talking for a while, and he was being very 'close' with me, as if we were a couple..
It's only when I suggest we do something (casually...), aside from meeting each other through friends (he's best friends of my housemate) that he suddenly freezes up and drifts away.