Rita is the vice captain of "Immortal Blades" and the trusted adjutant of Durandal, and one of three S-Rank Valkyries in Schicksal working under Otto. She is dubbed the Schicksal maid.
Not much is known about Rita as she is very secretive and discreet about sharing information. It is possible that only Durandal and the other Valkyrie members of "Immortal Blades" would have more personal information of her.
Reburn Chapter 2
After the events in Moonlight Throne, Rita was sent to St. Freya to supervise the Valkyrie Qualification Exam. This was actually a cover-up by Otto because he sent Rita to observe K423's situation.
Rita makes her first appearance in Chapter 8: Battle of Schicksal.
When Otto was at the Helheim laboratory to prepare the release of reawakened Sirin in K423's body, he sent Rita to assist Fu Hua who had just arrived at headquarters. Fu Hua expressed surprise at how Rita was not with Durandal like she always is. Rita mentioned as much as she wanted to be by Durandal's side, she had no choice because it was an order from Otto.
Himeko and Tesla encountered Rita when they were at the 3rd Terminal to perform combat missions. Tesla's red mecha was instantly destroyed by her. Fu Hua soon arrived and told them to surrender. When Rita was just about to deal a fatal blow, Fu Hua stopped her. Rita then agreed to temporarily detain them in Schicksal jail.
Fu Hua had overheard from Otto on how Theresa and the others were fighting against Sirin in K423's body and tried to leave, but Rita stopped her and told her not to interfere with Otto's plans. Fu Hua realized Rita was stalling the battle and Otto's real intentions and both parties were about to start fighting seriously.
Durandal stopped their fight before it escalated and then told Rita to let Fu Hua go as she understood the concept of fighting for the ones she wanted to protect. Rita then asked Durandal why she let Fu Hua go because she could die if she went there, and Durandal said that it was Fu Hua's own choice.
- Roßweiße is derived from the second part of the opera "Der Ring des Nibelungen", "Die Walküre", the last of the nine daughters of Odin.