The Château de Rouge was a facility which the Legitimacy Kingdom's corrupt nobles imprisoned commoners they don't like in, charging them with made-up crimes. None of the prisoners were real villains, including people who tried to report misdoings, people who tried to create negotiation groups for people who work hard but don't earn much, people who gave to the poor, people who crossed the nobles' paths or were considered a potential threat by higher ups, among others.
The prison was known as the Château de Rouge, partly because of how the hanging container cells resembled layers of grapes, and partly because of how innocents were locked up and made to suffer, having their blood squeezed from them.
During the last hours of March 21st, following the 37th Mobile Maintenance Battalion's first, unsuccessful attempt to destroy the Ame-no-Uzume, Quenser Barbotage infiltrated the prison in order to break Mariage Nightcap out, so she could find the enemy Object's weakness. Though the escape attempt was compromised, the Ame-no-Uzume attacked and destroyed the prison to eliminate the potential threat. Quenser and Mariage managed to survive the attack and escaped to rejoin with the 37th.