Pisces woman and cancer man-what do I do?

I'm a pisces woman and he's a cancer man. When we first met I didn't really think of him romantically but I was always very sweet to him, and he started to hit on me very subtly-jokingly asking me out, telling our boss that he enjoyed seeing me every day. I actually had a crush on someone else that we worked with when I first met him and was focusing more on flirting with that guy. But he started really growing on me, he would say really sweet things and stare at me all the time, stand around me but not really say anything, like he was too nervous or something. I haven't seen him in a while since we stopped working together, but I can't stop thinking about him and I can't shake the feeling that there really is something there. He seems so shy about it, should I just ask him out? Definitely not my style to ask a guy out(never had to do it!!) but it seems like the only way to really know...or is it better to give him a little space and let him come to me at his own pace?