The Private Room is William Afton's office and a secret location in Sister Location. It is only accessible on the fifth night's Fake Ending. It is accessed by disobeying Circus Baby, and going to the room on the opposite side of the Scooping Room. It is only accessible if the Baby Minigame is completed. HandUnit says you have wondered into a restricted area, and inicates it contains sensitive materials, as to why Michael Afton cannot leave until his rescue at 6 AM. Ennard then proceeds to hunt Michael, trying to get into the room, as well as emotionally baiting him to give himself up.
After surviving till 6 AM they get fired and sent home with a basket full of Exotic Butters as a gift while watching the last episode of The Immortal and The Restless. It is used as the main location in the Custom Night.