Men winking at you when saying hello

[leostar1994]

I work with a guy, we are both mid-twenties and every time I say hello he's either really smiley or winks at me. If he sees me walking back to work from town and we pass he will wink. Is this just friendly or is it flirty behaviour?

Next time he does it, ask if he's got a nervous tic or something wrong with his eye. That should stop him.