One of the reasons fans consider Attack on Titan to be one of the best series ever made is because of how much they like the characters. While they're all great on their own, whether it be due to the role they had in the story or how much readers could relate to them, Attack on Titan's characters were at their best when interacting with each other.

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Friendship is an important theme in many anime, especially shonen series like Attack on Titan. Considering how bleak and hopeless Eren's world feels, having staunch friendships is especially important. Attack on Titan has a wide cast of characters that allows for protagonists and antagonists alike to form close, meaningful bonds with others.

10 Reiner & Conny Went Through A Lot

Connie and Reiner

Reiner became close friends with Conny after he became a soldier, as the two of them were in both the 104th Cadet Corps and the Survey Corps. When it seemed that the Titans broke through Wall Rose, Reiner went to Conny's hometown with him. They discovered that the town was abandoned except for a Titan that Conny suspected was his mother. Reiner tried to console him to protect his own secret.

Shortly after, Reiner revealed himself to be the Armored Titan and Conny felt betrayed. Years later, the two join forces in order to save the world from the Rumbling. Afterward, the Jaegerists considered Conny a traitor and he finally understood how Reiner felt during his time in the Survey Corps.

9 Reiner & Bertholdt Were Close Comrades Since Childhood

Attack on Titan Reiner & Bertholdt Look Over Their Shoulders

Growing up as warrior candidates in Marley, Reiner and Bertholdt shared a close friendship. When it seemed that Reiner would be the only candidate that wouldn't inherit one of the Nine Titans, Bertholdt tried to make him feel better. Luckily, they inherited the Armored and Colossal Titans.

They went to Paradis not long after and Bertholdt followed Reiner's orders for years, looking up to him as the leader of the warriors. They acted as Paradis soldiers, and as Reiner started falling for his own act, Bertholdt became concerned for him. After the Survey Corps found out their true identities, Reiner and Bertholdt fought their former friends and were always loyal to each other.

8 Gabi & Falco Were Rivals That Cared A Lot About Each Other

Gabi and Falco

Gabi and Falco were the next warrior candidates that could inherit Reiner's Armored Titan once he died. While Gabi really wanted the Armored Titan to feel closer to her cousin, Falco wanted it so Gabi could live a long life, as he was secretly in love with her. Gabi was easily brainwashed by Marley but Falco understood that the Eldians on Paradis weren't so different.

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When she snuck onto the Survey Corps' ship, he followed her. The two of them were arrested after Gabi killed Sasha, but they escaped, and Falco was able to protect Gabi for a time. Once Gabi realized that everything Marley told her was a lie and Falco confessed his feelings for her, the two of them did everything they could to stop the Rumbling.

7 Mikasa & Armin Were Childhood Friends That Were Always On Each Other's Side

Mikasa and Armin

After Mikasa's parents died and she began living with the Jaegers, she became close friends with Armin. The two witnessed the Colossal Titan destroy their homes together and agreed to become soldiers. Mikasa's strength and Armin's intelligence made them a great team that worked well together.

Over the years, they proved their friendship many times, such as when Mikasa fought to save Armin's life after he nearly died by sacrificing himself to defeat Bertholdt. Even after it seemed that Eren completely betrayed them, they had each other's back and both played very important roles when it came to defeating him.

6 Hange & Levi Fought By Each Other's Side For Years

Hange Zoe and Levi Ackkerman staring at one another in Attack on Titan pre-timeskip

Hange was one of the first soldiers that Levi befriended when he joined the Survey Corps — a friendship that continued to grow stronger. They had been through a lot together, especially when they both became leaders in Paradis' military. Unfortunately, Hange's squad died in the battle against the warriors at Shiganshina.

After Erwin's death, Hange became the Survey Corps' commander. This caused Hange to work with Levi more than they ever had before since they were the only remaining soldiers with the most experience. When it seemed that Levi died, Hange rescued him and even sacrificed their life in order to allow Levi and the rest of their comrades to save the world.

5 Jean & Conny Got Very Close Over Time

Connie and Jean

Jean and Conny were friends for years but didn't get close until after they fought the Titans in Trost District, as many of their comrades died. Although they were two of the few soldiers from the 104th Cadet Corps that could have joined the Military Police, they decided to join the Survey Corps instead and were both in Levi's squad.

They had been through a lot together and ended up being inseparable, especially after their other closest friend, Sasha, was murdered by Gabi. At the end of the series, Conny and Jean watched as their friends fought Eren, knowing that they couldn't do anything to help them.

4 Levi &  Erwin Had Each Other's Backs Despite Being Enemies Initially

Levi-Erwin-Attack-on-Titan

Although they were originally enemies, Levi and Erwin became very close over the years. If it weren't for Erwin, Levi never would have joined the Survey Corps, and they ended up being an amazing team. Levi always had faith in Erwin and never wanted anything bad to happen to him.

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When they fought the Warrior Unit in Shiganshina, Erwin sacrificed himself to allow Levi to kill the Beast Titan but Levi failed his mission. Rather than saving Erwin with the Titan serum, he gave it to Armin instead, knowing the burden Erwin had to carry as the Survey Corps' commander.

3 Conny & Sasha Were Like Siblings

Connie and Sasha in Attack on Titan

Conny and Sasha had a lot in common and became very close during their years as soldiers. They didn't usually take things as seriously as their other friends, often goofing off or joking around. Due to their personalities, it was easier for Conny and Sasha to get along with each other more than anyone else, and even considered each other family.

Conny was devastated when Sasha died after they invaded Marley under Eren's orders. However, at the end of the manga, Conny, as well as Jean, was able to see Sasha one last time due to the Eldians momentarily returning after Eren was defeated.

2 Eren & Mikasa Always Loved Each Other

Eren and Mikasa as Kids from Attack on Titan

Eren's father and Mikasa's parents were friends with each other, and Grisha hoped that the children could become friends as well. When he brought Eren to meet the Ackermanns, they were shocked to discover that Mikasa was kidnapped and her parents were murdered. Eren saved her and the Jaegers brought her into their home, giving Mikasa a second family. Over the years, they became inseparable.

However, once Eren learned about what he'd do in the future, he pretended that he hated her so she and his other friends would save the world by fighting against him. Although she had to kill the person she loved most, Mikasa and Eren always cared a lot about each other.

1 Eren & Armin Would Have Done Anything For Each Other

Eren and Armin hug

Armin was Eren's first friend and they grew up together in Shiganshina. Unlike most people, they shared a common dream to fight the Titans and see the world beyond the walls that imprisoned them. Eren proved his bond with Armin when he first turned into the Attack Titan to save Armin's life.

Eren and Armin always helped each other out and would have done anything for each other, such as when Armin tried to convince the Garrison that Eren wasn't a threat, or when Eren fought to save Armin with the Titan serum instead of Erwin. However, like his other friends, Armin eventually had to fight Eren in order to save the world.

NEXT: Attack On Titan: Armin's 10 Closest Friends, Ranked