Is he after something?

I have just quit working at a company with a guy whom I had a bit of innocent fun with. He would come up from behind and tickle me a few times a day. When I announced I resigned, he wasn't happy, saying he'd miss me. I too missed him, we had fun. So I decided I'd visit for coffee twice a week before I'd begin work. The first time he asked for my number in case I ever wanted to return. He said for me to contact him if I wasn't liking my new job, and I did. He messaged back for me to visit the following morning for a chat and hug. 10 minutes after I left he messaged me that he missed me already. I replied saying I missed him too and he said that it's good to know I like seeing you. He called me a day later to see how I was. One of the guys at my new work reckon he's trying to root me. It's been playing on my mind because he's a married man with two kids. I just can't imagine he would be interested in me...
Is he after something?
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