Anka Rheinberger (アンカ・ラインベルガー Anka Rainberugā?) is a member of the Garrison and one of Dot Pyxis' escorts, the other being Gustav.
Anka appears in the residence of Lord Wald, accompanying Dot Pyxis along with Gustav. She watches as Pyxis plays chess, losing on purpose, seemingly to satisfy the Lord. At that moment, a soldier barges into the room, announcing that the gate in Trost District has been breached by the Colossal Titan, much to Anka's surprise. Despite Wald's protests, Pyxis readies to leave, followed by Anka and Gustav. Anka then goes on ahead, telling Pixis that she will ready his horse and leaves
Later, Anka arrives to the Trost District with other soldiers just in time for Pyxis to stop Kitz Woermann from killing Eren Jaeger. After Pixis listens to Eren's words and gets him to help with plugging the Wall, Pixis calls for staff officers to formulate a plan, Anka being one of them. While Pixis announces the details of the upcoming plan to other soldiers, Armin Arlelt discusses the plan with Anka and Gustav. During the discussion, Anka states that Titans are not the only enemy, correctly deducing the current state of soldiers' mind.
During the operation, Anka, along with the other soldiers, watches the progress from top of the Wall. With Rico Brzenska firing a red smoke signal after Eren loses control, Anka proposes to pull the elite team back, but Pyxis refuses, trusting the elite team as they're the only chance for humanity. Once Eren regains the control and successfully plugs the Wall, Anka sees the signal and announces it to the rest of the soldiers.
Clash of the Titans arc
Anka is seen on top of the Wall in Trost District during the supposed breach of Wall Rose. She wakes Pyxis up, scolding him for sleeping there and drinking alcohol, given his advanced age. She states that she does not want to be stuck taking care of him, much to the amusement of Pyxis, who says he would want nothing more than such a beauty doing so. Anka then reports to him that new Titans stopped appearing at the first and second lines of defense, but the search party only found a few as well. This makes them wonder about the situation, given the fact that if there was a breach, the amount of Titans appearing would be much higher. Anka then watches as Erwin arrives to talk to Pyxis. Later, Anka is also by Pyxis' side when the Vanguard reports back that there is no breach as well as about the situation that occurred with Reiner and Bertholdt.
While not directly seen in action, it is presumed that Anka possesses enough skill as a soldier to be the escort of Dot Pyxis. However, her main focus seems to be strategizing, with Anka's intelligence being high enough to formulate a battle plan while quickly evaluating the situation and predicting further circumstances. A sign of her abilities may be that the original duty of strategizing was entrusted to only her and Gustav implying Pyxis trusts her enough to come up with a strategy that saves not only Trost, but humanity as well.