Tsuzumi Mansion

The Tsuzumi Mansion (の) is a large house controlled by Kyogai located in the south-southeast. It is the titular setting of the Tsuzumi Mansion Arc.

Synopsis
The Tsuzumi Mansion was originally Kyogai's home while he was human and has been his base of operations since transforming into a demon.

Each room is controlled by Kyogai's Blood Demon Art in different ways. They can be flipped different directions or anyone inhabiting them can be transferred between rooms. While Kyogai's Blood Demon Art is active, running around the hallways of the mansion will only lead someone in circles.

Tanjiro and Zenitsu arrive at the mansion after being given orders to defeat the demon who lives there. They bump into a pair of siblings who ask them to help find their brother, as well as another Demon Slayer in a boar mask.