Hange Zoë

Hanji Zoe (ハンジ・ゾエ) is a Squad Leader from the Scouting Legion. They conduct research on Titans and, as such, are deeply interested in Eren Jaeger, who can turn into a Titan.

Personality
Hanji is very passionate about their work. They can be seen as very hyper and very active, often diving into their work without thought for personal safety and documenting the experiences. However, their lectures are very boring and astute soldiers quietly leave the room before they begins one.

Hanji is often excited by Titans and is always eager to experiment with them, coming off as extremely emotional regarding titans. For example, they cried at the amount of pain they were giving a titan during one of their experiments.

They explained their strange actions to Eren as a way to see titans from a different perspective and learn new insights that would normally be overlooked from the traditional views of rage.

However, Hanji still cares deeply for humanity and their comrades as seen  when they confronted Pastor Nick for his coverup of the Wall. When he refused to talk, they personally grabbed him and held him over the side of Wall Sina, explaining that lives were lost because of him and his religious faction and that they hold him in utter contempt.

(Not part of Hanji's personality, but important to note is that Isayama Hajime never specified what gender Hanji indentifies as; Levi uses gender neutral pronouns when addressing Hanji, and many translators have overlooked this. Also important is that even though in the anime, Hanji has physical qualities that many people associate with being female, appearance does not equal gender, and so therefore, using female pronouns can be seen as problematic and should be avoided.)

Current Plot
Hanji Zoe is introduced when they take Eren to his military hearing in front of the leaders of the human military. They are present with the rest of the Scouting Legion as Rivaille beats up Eren and checks on his condition after the tribunal is over, noting that the gap where Eren lost his tooth earlier is fast disappearing.

All of their experiments with captured Titans "Sonny" and "Bean" turned up no vital evidence which is why Hanji is so excited to work with Eren.

Later, when Eren and the Special Operations Squad are at the former Scouting Legion HQ, they begin to prep Eren on their experiments, but ends up talking until morning when they are interrupted. Hanji was about to talk about the curious precedent involving Ilse Langner when it was discovered that Bean and Sonny were murdered.

Although devastated by the loss of their test subjects, Hanji moves forward with their experiments on Eren. When it turns out Eren cannot turn into a titan at will, they are a little disheartened. However, seeing Eren's titan hand later on got them very excited, unexpectedly breaking the tension between Eren and the Special Operations Squad.

They discovered that Eren's titan powers are only awakened when he has a clear objective in mind, such as defending against the cannonball. They also theorized that this switch must have a good reason as well as being connected to the titan's nature.

They stop Keiji from continuing to try and open the crystal Annie Leonhardt put around theirself to avoid capture. They direct their men to take it away quickly when they notice the titan within Wall Shina.

Before they can react, Pastor Nick hurries to them and tells them to stop sunlight from hitting the titan's face. After this, they try to question the Pastor about what they had just seen, but he roughly tells them they do not need to know anything about it and even threatens compensations for damages done to his church.

Furious at his attitude, Hanji pulls Nick over the edge of the Wall and threatens him to tell them why there are titans inside the Wall. They come to the conclusion that the his religion has been so opposed to Wall modifications because of what they know is inside the Wall. They explain that the people of the Scouting Legion sacrifice their lives hoping that one day, it will mean something. Thus, they have a right to know what they saw and why it is there.

However, Pastor Nick is willing to die to maintain his secrets and Hanji decides to let him live. He finally tells Hanji and the other members of the Scouting Legion about Historia knowing more about the walls having titans in them. She went under an assumed name after she was caught in the middle of her relatives dispute and will tell them more about it, if she choses to.

After Hanji's squad rescue the Scouts trapped at Castle Utgard, Hanji tells everyone that it's time to go. The Scouts begin to leave. After seeing Mikasa try and kill Reiner and Berthold, Hanji proceed to attack the colossal titan and holded up well until it exerted burning gas.