This is a hidden basement room, derivable to so if your a creator make your own custom version!

Its like an extra room you can add on to an existing room you have.

The room is underground about 25 feet down from any furniture node you have it on, it has 4 standing spots and has its own 25 floor position furniture nodes. Easiest way to get furniture down there  is go down to the room first! then add your furniture.