White Room

The White Room (白の部屋) is an extra-dimensional space strongly connected to the Selector battles. After her death, Mayu came to inhabit the room as a spirit, and it is here where she monitors the Selector battles. Here, Mayu receives Selectors who have become Eternal Girls and are soon to become LRIGs.

In a bid to end the Selector system, Rūko Kominato confronted Mayu in the White Room with Yuki, who battled against Mayu and Ulith. After Mayu's defeat, the White Room seemingly disappeared. However, the emotions of the Selectors that had suffered under the previous system coalesced into Eternal. Due to Tama and Yuki's continued existences, the White Room continued to exist.

Throughout the second Selector system, the White Room was used to recruit new Selectors, who would meet the LRIG of the Beginning. Whenever a Selector's memories and personality disappear in accordance with the system's rules, their memories would be stored as coins inside the White Room.

After the end of the second round of Selector battles, Eternal began the third round of Selector battles, seeking a new master for the White Room to continue the Selector battles. The third system was designed to have a singular winner, who would then enter the White Room and assume their duties as its new master. Kiyoi Mizushima become the winner of the third round, but she chose to confront Eternal. After Kiyoi defeated Eternal, the White Room ceased to exist.