Petra Ral

Petra Ral (ペトラ・ラル) was a hand-picked soldier from the Scouting Legion by Levi in the Special Operations Squad.

Personality
She looks up to Levi as a captain and cares strongly for her team, though notably at odds with Auruo.

Petra is kind and caring, as shown when she looks after and guides Eren when he is first admitted to the squad and seems to have acted as some sort of attachment figure for Eren among Levi's Squad as she is the one shown to worry most about him as well as wishing he would rely and trust her and the others, and it is ultimately her who had managed Eren to do so. Whatever the case, Petra's words had a major impact on Eren. It should also be of note that the biggest reaction from Eren over the deaths of the Squad was in regards to her.

She also showed the most remorse over the reaction of Eren's accidental transformation.

Petra: "We're sorry Eren. We got scared and did something stupid and you must be disappointed in us."

Along with her comrades, she had bit her hand just like Eren, signifying that they had established a bond which was proven as very strong as Eren was shown to have been deeply hurt over their deaths and blaming himself for it.

Story
Petra is first introduced during an expedition outside Wall Rose, tending to a mortally wounded soldier. When she was unable to stop the bleeding, she helped Levi comfort the dying youth and wept openly at his death.

She is later selected to become a member of the Special Operations Squad and ordered to guard Eren Yeager. It is established that she greatly admires Levi, and argues frequently with Auruo Bossard over his imitation of their commander and his harsh behavior.

While initially wary of Eren and quick to draw her swords when he transformed by accident, she readily accepts him afterwards. She is the first of the group to bite her hand in imitation of Eren's method of transforming, and notes that doing so is actually quite painful. She serves as a gentle, almost maternal presence within the squad and discusses with Eren the importance of trusting one's comrades completely.

When the Female Titan begins her attack on the 57th Expedition, Petra is one of those most vocal about Eren avoiding battle. She repeatedly begs him to trust in his commanders and comrades, and accept the sacrifices of others so that the mission can continue. Eren eventually makes the decision to follow her advice, allowing the Scouting Legion to successfully capture the Female Titan in a trap. Afterwards, the Special Operations Squad is ordered to standby while efforts are made to capture the human within the Female Titan. However, the operation ends in failure when the Female Titan uses a scream to summon other Titans to her position and is devoured by them.

Afterwards, the squad begins to retreat back to their horses, when a flare leads them off-course. They are then ambushed by a person later revealed to be Annie Leonhardt, who murders Gunter Shulz before transforming back into her Titan form. Eren is ordered to flee while the surviving squad members engage the Titan in battle. Petra and the others initially seem to have the upper hand, first blinding the Female Titan before crippling both her arms. But when Petra and Erd Gin move in for the kill, the Titan suddenly regenerates a single eye and kills Erd.

Death
Paralyzed from the shock, and despite Auruo's pleas, Petra is unable to react in time to the Female Titan's attack, which breaks her spine and splatters her against a tree. In the anime when the Scouting Legion is returning home from the exhibition, the surviving soldiers are being chased by Titans and in order to escape, Levi orders the troops to abandon the bodies of the deceased so that the weight would be lifted off from the wagons. One of the bodies that were disposed was Petra's, whom Levi was watching over.

Her father comes to greet her when the troops return, briefly stopping to speak with Levi about his daughter. He reveals that she wrote to him constantly, and that she had great pride in being selected as a member of the Special Operations Squad. The words full of admiration toward Levi she wrote in her letters, bring her father to want to marry her off to Levi in the future, expressing concern that at the moment she is still too young for a serious relationship and that she had the whole life ahead of her for that. Levi remains silent throughout the conversation and it's not shown when Mr. Ral was informed about his daughter's death.

Abilities
She was a skilled and experienced warrior and had a high kill record of Titan kills (58 Titan killed, 48 in team and 10 in solo), being the highest known in the series so far.

Relationships
Levi - Petra greatly admires Levi. This causes her to be with odds with Auruo due to Auruo imitating Levi. When Eren accidentally transformed into a Titan, she was more concerned about Levi's life rather than Eren. It is unclear if she had romantic feelings for him or if it was just hero worship. However, in a conversation between her father and Levi, it was implied that Mr. Ral wanted Petra and Levi to get married one day thinking of him as a good match for his daughter.

Eren Yeager - She was the who watched over Eren the most and was the one who managed to get Eren to trust them. She also showed the most remorse over Eren's accidental transformation. Also, Eren's had the biggest reaction in regard to her death than the other members of the Special Operations Squad.

Special Operations Squad - Petra cares greatly for her team and trusts them. Although mostly at odds with Aurou.

Trivia

 * Petra is the only female in the Special Operations Squad led by Levi.
 * Her name is Greek in origin, meaning "rock" or "stone" and is also the name of an ancient city in the region that is now Jordan.