Frieda Reiss

Frieda Reiss (フリーダ・レイス) was Rod Reiss' eldest daughter and Historia's half-sister. She is known to appear in Eren's and Historia's dreams.

Appearance
When he dreams of her, Eren first mistakes her for Historia, which shows that they must look similar. She has long smooth dark-coloured hair.

The Uprising arc
She appears in Eren's dream, with him seeing her from her own perspective, while she looks into a mirror. In Historia's dream however, she actually interacts with Frieda. She teaches Historia how to read and tells her to become a kind person. Frieda appears moved when Historia claims that she wants to be like her and then proceeds to manipulate Historia's memory, telling her to forget about her until they see each other again.

While Hange and the new Levi squad attempt to search for Eren's location, Hange reads a report commissioned by Erwin on the Reiss family grounds. Hange explains that Rod's eldest daughter Frieda was loved by all in their village for her genuine character. She was even known to visit the fields to thank the farmers for their work. A tragedy struck the Reiss family the night Wall Maria fell, and when bandits supposedly raided a chapel in the village, the entire Reiss family save for Rod and Historia was murdered.

However, it is revealed through Eren's memories that the one responsible was actually Eren's father, Grisha. Grisha in his Titan form slaughtered and ate Frieda and her family while they were hidden in a basement under the chapel, getting their memories. When Eren ate Grisha, Frieda's memories were transferred to Eren along with Grisha's.

Abilities

 * Memory Manipulation: She is shown to be able to manipulate the memories of a person, when she had Historia forget about her.