Is this guy just enjoying the ego trip?

If he has a girlfriend & he is flirting with you & being extra attentive, then that really tells you what he is like, if he is doing that to her, then he would do the same to you. Be friendly & have fun but there are plenty of single guys out there & I wouldn't feed his ego as he does seem a bit full of himself & maybe he thinks he is in with a chance with you & I wouldn't mix work & fun time as it would only make things so awkward for you at work............ he seems like a player.......... if he liked you enough he would sort things out with his girlfriend before he got involved with someone else.....be careful or you may get hurt.........