Luigi only visits this room after defeating an area boss in the mansion. Like the Lab, Luigi cannot freely roam around the location. The final cutscene takes place in this room, which shows Mario being transformed from a painting and into his normal self.
There is a door at the very right of the room. Although it cannot be entered, this door leads to the Gallery (according to the Game Boy Horror). Another door also appears at the start of the room, which leads to the Lab, although it is not visible.