Silent Room
A Silent Room is, in short, a room hosting a contained anti-magic field. An Officio's headquarters will have many such rooms, and they may be found in some of their other compounds as well, especially research facilities, or cells specializing at hunting rogues.
Since there likely isn't a Culexus gem under each of these, it must be assumed that anti-magic fields can be produced industrially. The rooms have a variety of settings, mostly pertaining to how strong the field should be. Depending on the inhabitant's status, the room may be organized as more of a jail cell even with inbuilt defenses, or may instead be organized as more of a living room, or an outright laboratory. Certain Silent Rooms are special enough to have names, such as the Ninth's Silent Room Regalia, meant to contain extremely powerful Maerorus.
Practical Use
Officios use Silent Rooms for a variety of purposes, the most obvious one being holding cells for Magical Girls. Since escape from a regular jail cell would be easy for a girl who can bend iron bars, smash brick walls, turn invisible, or just teleport outside, it is necessary to first impair her abilities. Only then may any attempts at reasoning with her begin. Prolonged prison sentences are not a norm, however, since a girl stuck in a Silent Room is a girl not working for her Grief Seeds.
Less often, the cells are used to enforce a quarantine, for example, if the occupant has recently spent a long time in the Akashic Realm, or is subject to a powerful spell with a set duration.
Weak Silent Rooms may be used to stabilize powerful magic - for example, Prognostication performed by non-Culexus, as demonstrated by Haruka Amane. Venenum may also use Silent Rooms as a fallback option when experimenting with dangerous magical materials.
If something is being sealed, like a powerful artifact, a Silent Room may be a part of the seal. A Grief Seed stored in a Silent Room will also keep for much longer, as the Witch has trouble regaining her power.
Trivia
- Affinity and strength required to subdue the girl vary among people, with most fitting somewhere around the middle. Certain Magical Girls have a slight affinity towards Culexus (such as Sakura Kyoko in the main story), and tolerate them more easily, thus requiring a stronger room if it came to it. On the other hand, someone like an imperfect Maerorus with parts of a Witch in their body would feel relatively more pressure than others.