He's only been in town a short time so far, but I'm sure since both aspects of his life could involve Emil, they already know each other fairly well. And it'd be kind of hilarious to see Izzy hit on him since he wouldn't know at all what to do, especially because he probably isn't overly fond of her. xD
I like the idea that he knows Holland from some time in the past. I never specified where he spent all of his time hopping around, so its entirely possible they met in England or in Ireland?