Sister Thornly's School for Wayward Tots is an orphanage for children with no home or family. It is where Otto Osworth once lived.
The orphanage is a run down Victorian styled house surrounded entirely by the inner city of an unspecified metropolis in the United States. The property itself is surrounded by barbed wire and is always locked, with the idea to keep the children in and less about keeping others out. The yard has brown patches of grass and everything else is muddy. And people seem to treat the property as a vacant lot to throw their junk away.
Inside the house, it is dirty and in need of renovation. Broken glass, peeled wallpaper, and dead rats are just some of the things that are shown through out place.
The size of the house and how many rooms there are is to speculation. It's shown that Otto's bedroom was located in the orphanage's basement, and he had a room to himself. With 32 other kids living with him, it's not clear if the house can comfrortably fit a room for each child or not.