Technically a toilet
When you’re searching for a house or apartment to buy or rent, you probably have particular criteria. You may need at least 3 bedrooms or a garden for your children to play in. You might not be able to deal with stairs, or you might have to have a garage for your bike.
You may search for houses that have 2.5 bathrooms, and then this little gem (or something like it) would pop up in your search. Technically, this is the room that makes this house a 2.5 bathroom home. I dare you to try and pee in it, though. Seriously, how cheeky are some people?