I haven't heard of them until I accepted their shop.
My shop went very easily, I was happy to see that Target and Walmart are stores that can be shopped through Klarna.
My shop was accepted and paid before my second "payment" was due so I just logged in and paid the rest in full.
I agree it's strange to split a $40 purchase into four payments but I suppose some people might need that. It approved me quickly and didn't ask for any information to have to do with my credit score or anything like that.
Hope that helps!