Breaking Down Eren and Levi’s Relationship
Description
Eren Jaeger is the main character of Attack on Titan and grows from an idealistic, wide-eyed boy to a jaded anti-villain who loses himself in his own obsessions. Levi, his mentor figure, is a captain in the Survey Corps, who grew up in poverty in the underground “dog-eat-dog” society.
Both found themselves loyal to the Survey Corps for fundamentally different reasons, but with a similar goal: freedom. However, how they each “defined” it was a different story. As Eren became exposed to the reality of his situation and the truth of the outside world, Levi trusted that Eren would steer humanity towards a better path.

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Seeing The Best in People
Levi’s Mentorship
Eren always idolized the Survey Corps, wanting to join despite his mother’s wishes, since he was a child. As Levi was the captain, Eren admired him significantly to the point where he ended up fearing him altogether after a staged trial before his first expedition. However, Levi had confidence that Eren had the ability to move humanity in the right direction, and he was spot on, to an extent. As he taught Eren that there’s no way to know the outcome of a decision before it’s made, this leads him down a path where things are taken to a literal level.
During the encounter with the Female Titan, Eren is insistent on transforming, while the group is running through the forest. Levi gives him the option to trust in his comrades or rely on himself. He makes the decision to trust in his comrades the first time, leading to the initial capture, but the second time, all of Levi’s squad dies due to a surprise attack from Annie. This signals back to an OVA centered around Levi, “A Choice With No Regrets”. It’s best to regret something you did do, rather than a chance you never bothered taking.
In a poetic scene of events, Eren chooses to “rely” only on himself and stage an attack on Marley to commit The Rumbling, thus making a decision that he regrets. However, it was a decision that Eren already knew he was going to make, and seeing how he lamented his mistake in the end, Eren regretted not allowing himself to find other possibilities (such as Marley’s complicated relationship with other countries, which could have led to possibilities of trade/alliances with other nations, aside from relying on the Azumabitos, who were untrustworthy) and inadvertently limiting himself to a single future. In other words, he made a choice that led to him both regretting what he did and what he didn’t. Something of interest is when Levi makes an observation of Eren after the Liberio raid, when he states that the latter has the same “eyes” as those of the underground. It can be theorized that Levi rubbed off on Eren in more ways than one, and, with Eren’s tendency to be narrow-minded, he took his advice literally.

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Humanity in Disappointment
As the story progresses, Eren goes from a stray human-titan hybrid, to a subordinate, to an estranged protégé. Levi had been arguably proud of Eren at one point. Despite his tough exterior, Levi genuinely cared for all of his comrades, including Eren. Some fans call him and Hange the “parents” of the Survey Corps, and rightfully so, as they play a part in raising them both as soldiers but also to remember to hold onto themselves. Eren, in his inability to compromise, lost himself.
Hange and Levi were both left to pick up the mess, with Levi doubting his choices to cover for Eren as much as he had been, as seen during his battle in the forest with Zeke. In the end, Levi had to clean up Eren’s mess, along with everyone else, resulting in the latter’s death. Ultimately, Levi was like a second father to Eren, but was “betrayed” by his own “son”.