Ilse Langar (イルゼ・ラングナー,Iruze Rangunā?) was a member of the Survey Corps. She was a participant of the 34th Expedition beyond the Walls and was in charge of the left wing of the second brigade. She wrote very useful information about her final moments in a notebook.
Ilse was noted to have resembled Ymir in appearance. She had short black hair that was parted to the right side, and gold colored eyes with a small patch of freckles below each one. She wore the standard Survey Corps uniform and cape with a grey shirt underneath.
She appeared to be quite emotional, yet brave. She seemed to be a very devoted and smart soldier, speaking that she must not let fear over come her, that she is humanity's wings of freedom, and has been prepared to face her struggles ever since she joined the Survey Corps. She also appeared to think about others, even when she was in grave danger. During her last moments she regretted not being able to give anything back to her parents. She thought of herself as a proud member of the Survey Corps and was resolved to do whatever she could.
During the 49th Expedition outside the Walls, Hange Zoë among other members of Levi's squad encounter a Deviant Type Titan that, after chasing Hange, turned the other direction and headed farther into the forest. Hange follows it to a forest clearing where it head butts a tree. It is soon killed by Levi after almost eating Oluo Bozado. Petra Ral points out a decapitated corpse hidden in a hole in the tree, and they find a hidden notebook that belonged to Ilse Langnar before her death.
Hange reads the notebook. It explains that after Ilse's entire flank was massacred, with her horse lost and her Three Dimensional Maneuver Gear broken, she abandoned her gear and fled north to a nearby forest. After profuse running, she inadvertently runs into a Titan and writes in the notebook, believing it to be her end. She remarks that instead of immediately eating her, it hesitates and she questions if it is an aberrant. It then addresses her, saying "Ymir's people" and "Ymir-sama", greeting her with deep respect, and bowing.
She is thoroughly confused that the Titan can form speech, and writes in her notebook that she attempted communication with it. She first questions it about what the Titans are and then about where they came from. After building up sadness, fear, and rage, she angrily yells at it. Asking why Titans eat humans and what their objective is; calling them useless lumps of flesh that should disappear from the world. The Titan appears more and more frustrated as it moans and begins to tear off its cheeks, ripping off flesh and spraying blood. Horrified, Ilse attempts to flee but is quickly caught by the Titan, who begins rapidly crushing her skull with it's teeth. Ilse frantically writes down her last few notes about the experience before her head is crushed and then bitten off. The Titan later stores her corpse in the tree. Nothing is known about the Titan's reasoning for its actions, but Ilse's notes become significantly useful to humanity.