Windowless Room

The Windowless Room is a room located within a certain Anti-Skill station, where Board Chairman Accelerator dwells following the start of Operation Handcuffs.

Principles
The secret room is located deep within a certain Anti-Skill station. Not found on any official diagrams, it is an interrogation room used for cases requiring utmost secrecy before law enforcement makes its move and where a minimum number of officers make final checks before beginning actual investigation of large-scale corruption, bribery and other similar crimes.

It is a small room, without windows, only containing a clear table and two cheap chairs. There is an inner door leading into the room, locked by rods, and a large outer door with composite armor, with a cramped space between them. The two doors provide extra security but also prevent guards from spying on the interior.

Christmas Eve Arc
On December 24th, Yomikawa Aiho met with Board Chairman Accelerator, who had turned himself in to Anti-Skill for his past crimes as part of Operation Handcuffs, his plan to eliminate the Dark Side of Academy City, in the 'windowless room' and discussed the imminent operation. He remained there during the attempt to kidnap Last Order by individuals seeking to preserve the dark side and the subsequent battle against them, despite being easily capable of breaking out and ending the matter himself, choosing to believe in the city he was to lead. Yomikawa left, after Misaka 10032 brought Last Order to the safety of the station, to participate in the operation. After the incident was resolved, Last Order visited Accelerator and tearfully accepted his decision, with Qliphah Puzzle 545 present nearby.