The Female Titan is one of the strongest beings in Attack on Titan's universe. It could possess the abilities of the other Nine Titans, such as hardening and being able to control normal and abnormal titans.
Throughout the manga, there was only one character that had inherited the Female Titan, Annie Leonhart, though there were many who came before her. While there are many benefits to inheriting the female titan, Annie had a very tough life precisely because she became a titan shifter.
10 The Female Titan Was Hated All Over The World
Due to the Eldians using the Nine Titans to conquer the world, other races hated the Female Titan for centuries. After Marley was able to obtain them during the Great Titan War, the Female Titan, along with the Beast, Jaw, Armored, Colossal, and Cart Titans, were used to fight Marley's enemies, including the Eldians in Paradis who were nothing like their ancestors after Annie inherited it. The Female Titan became one of their greatest enemies, and they both feared and hated her.
9 Each Inheritor Died Within Thirteen Years
Like every other titan shifter, those that inherited the Female Titan died within thirteen years. If they hadn't been eaten by a successor by the time their term was up, they would die and an Eldian infant would be born with its powers. This was because Ymir Fritz, the Founder, was killed thirteen years after coming in contact with the Source of All Living Matter. Annie was the first inheritor of the Female Titan to live beyond thirteen years due to the titans' extinction at the end of the manga.
8 Annie Was Adopted By An Abusive Father
After Marley obtained most of the Nine Titans, the Eldian children who lived there were trained to become warriors in exchange for them and their families becoming honorary Marleyans. Wanting to be an honorary Marleyan himself, Mr. Leonhart adopted Annie and taught her how to fight from a young age. He never showed her any love and constantly forced her to train, hoping that she would have what it takes to become one of Marley's warriors.
7 She Became One Of Marley's Warriors
Annie's training eventually paid off once she became a warrior candidate and inherited the Female Titan shortly after. She was used as a weapon for Marley to defeat its greatest enemies.
After destroying an entire nation, Marley sent her, along with Reiner, Bertholdt, and Marcel, on a mission to Paradis in order to take the Founding Titan. Before she left, Mr. Leonhart apologized to her and told her that he wanted her to return home, but it was too late.
6 Annie Continued Her Mission Despite Not Wanting To
Once they arrived on Paradis, Marcel was eaten by Ymir, who inherited the Jaw Titan, while Annie, Bertholdt, and Reiner ran away. Though Annie wanted to return to Marley and see her father again, Reiner didn't want to fail their mission and convinced her to keep moving forward. They invaded Shiganshina and started new lives shortly after, deciding to join the 104th Cadet Corps and become soldiers in the Military Police so they could get close to the royal family.
5 Reiner Had Her Do A Lot Of Work While He Barely Did Anything
During their time as soldiers, Reiner had Annie do a lot of important work while he and Bertholdt simply befriended their comrades and trained with them. If it weren't for her, they wouldn't have known anything about Paradis' true royal family, as she had investigated the Military Police, Kenny Ackerman, and the church, hoping that it would lead to discovering who the Founding Titan's inheritor was. Little did the warriors know that they were close to him the entire time, every moment that they trained with Eren.
4 She Was Forced To Kill Marco With Reiner
After graduating from the 104th Cadet Corps, the warriors invaded Trost District, letting the titans get inside it. When Reiner and Bertholdt talked about their mission, revealing their true identities, Marco overheard them.
This resulted in Reiner feeding him to a titan. Because she showed loyalty to the soldiers they trained with for years, Reiner had Annie prove that she was still on Marley's side by making her help him remove Marco's gear. As the three warriors watched their friend get eaten, they cried but knew that if they didn't kill him, everything they had worked for would have been for nothing.
3 Armin Discovered Her Identity
After Marco died, Annie stole his gear so, during an inspection, nobody would find out that she had killed two captured titans that the Survey Corps experimented on. However, Armin knew exactly what Marco's gear looked like due to how close they were and noticed that Annie had it. When he thought about that, along with how the Female Titan looked like her, fought the same way as her, spared his life, and knew what Eren looked like, he discovered who Annie really was.
2 She Was Trapped In A Crystal For Years
After fighting Eren and Mikasa, Annie knew that she couldn't escape from the Survey Corps, resulting in her using her hardening abilities to form an indestructible crystal around her body. For years, she stayed in there and was conscious the entire time. Besides Hitch and Armin's company, Annie was isolated from the rest of the world for a long time, not knowing what was happening to her comrades. Luckily, she'd eventually get out.
1 Annie Thought That Liberio Was Destroyed And That Her Father Died After Eren Began The Rumbling
Years later, Annie escaped her crystal when Eren temporarily unhardened everything in existence to begin the Rumbling. He used the Colossal Titans inside of Paradis' walls to flatten most of the world, killing thousands of people. Annie and the other warriors believed that their nation was destroyed and their families were dead. However, when they teamed up with the Survey Corps to fight Eren and save the world, Annie found out that Mr. Leonhart was still alive, and they finally reunited.