A Trapdoor can be built in the floor space hotspot of the Throne Room in a player-owned house. The trapdoor's look will match the look of walls in the house, e.g. a trapdoor in a house with fancy stone walls will have a similar appearance.
When the lever is pulled, any players standing on the trapdoor will fall down into the oubliette below the throne room. When this happens, they hang in the air for a second and look down before falling, in the classic cartoony style.
Performing most emotes will delay a players falling through the trapdoor until the emote has ended. However, if timed correctly, some lengthy emotes (like Give Thanks) can prevent a player from falling through altogether.