How can you tell if a guy is flirting or just being playful?

Anonymous
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How can you tell if a guy is flirting or just being playful?
I may have a teeny tiny work crush.

This dude was one of the first people I met at my current job. We work right next to each other. He showed me around, and was really nice.

He's funny, and easy to talk to, and people tend to like him. He teases me a lot, in a lighthearted kind of way, which I think might be flirting. But at the same time, I've seen him do it with other people too. He does it a lot more with me, but a lot of guys tend to do that with me, because I'm a bit awkward, shy, and giggly.

He goes to all the get togethers after work, and gets along really well with all the people there. He seems to enjoy himself. But apparently he never went to those before I started inviting him. He started working with this company a few years before I did, and was always invited, but never attended. My coworkers apparently used to think he was standoffish, which surprised me.

At the same time, Mr. Dude never sits with me and my friends at meetings. He always comes up and talks to me individually before and after all the meetings, and occasionally sneaks up and whispers jokes to me during them, but then he sits by himself.

I don't know if he's flirting, or if he's just playful and we're friends. He seems social when he's around people, but he tends to turn down social offers, except when I started inviting him out for drinks. Maybe he just talks to me more because we work right next to each other, so he knows me better, but he started doing this pretty shortly after I started working there. He had been working with everyone else for a few years.

It seems like flirting. But I'm awkward, and not 100% sure. I don't even know what I would do if I was sure, but I'm curious.

Thank you!

P. S. I'm being intentionally vague about what I do for work, for privacy reasons, but it isn't the sort of job where it's inappropriate to date coworkers.
How can you tell if a guy is flirting or just being playful?
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