[halis123456789]

I play in a 2-5 NL game regularly, I've actually seen this type of flip move before (and don't really understand it.)

Anyway, you're getting 1.5 to 1 on your money so why call (esp. when he's moving in on a nothing pot?) If he has an 8 then surely there are easier ways to suck money out of you. It seems like he has something, but he is trying to protect it. The only things that come to mind would be A6 (but that's pretty loose PF), or possibly JJ or QQ.

If he's really the type of player to push all-in on a nothing pot with a flush draw or two big cards, then you'll find a way to take his money anyway.

I think it's a fold.