It looks like there's a few... Sometimes buildings from our worlds show up here, but if the person who came from that world decides to leave, it sticks around.

I was looking at the records when I checked out this place - it seems that's why there are so many of them.

And as for registering-- you're right. All we need to do is go into the city hall and claim it. It looks like they're fine with giving the buildings away!

[They must be desperate to get people to take them.]