Summary
- Mikasa’s good actions and honest intentions inspired others, like Louise, to follow in her footsteps.
- Mikasa’s mutual love for Eren led her to make tough decisions and end the Rumbling.
- Mikasa’s gratitude towards Ymir for the lives she gave birth to, led to Ymir finding closure.
Mikasa Ackerman is the poster girl of Attack on Titan and Eren’s love interest. Throughout the course of the story, her actions and behavior towards Eren sparked the interest of Ymir, the young enslaved girl from 2,000 years-ago, who was unsure of her own feelings towards her captor.
As a result, Ymir frequently peaked in her head, trying to understand Mikasa’s feelings and motives for her decisions in search of an answer to her own dilemma. She ended the 2,000-year-long curse after taking the life of her most beloved, but Mikasa was a hero to Ymir in other ways too.

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Good Actions with Good Intentions
Mikasa didn’t just have her own agency, but also looked out for others. In season 1, she kills an abnormal Titan that was headed for a group of civilians. A little girl, Louise becomes inspired by Mikasa’s bravery and opts to join the Survey Corps to follow in her footsteps. Though her devotion was not one of true admiration or love, but idealism.
The younger girl joined the Survey Corps and stood by the Jaegerists, despite their flawed outlook and cruel actions towards other civilians. Mikasa, seeing this, no longer recognized the little girl who she rescued all those years ago. Louise wasn’t following Mikasa, but an ideal, still believing her to be the same person who was unaware of the reality they lived in 4 years prior.
As a result, she pushed Louise away, voicing her disappointment through her actions, taking her scarf back, and only looking back solemnly as the latter succumbed to her wounds. Mikasa wouldn’t take advantage of a girl with a faux “devotion” to her, unlike King Fritz who took advantage of Ymir. Even if it was cruel, she wouldn’t give words of affirmation for the sake of an ulterior motive – most of all, she was honest.

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Love vs Obligation
Eren doubted Mikasa’s love for him, as he frequently lamented his flaws and put himself down throughout the course of the series. As Ymir watched over both of them, it’s safe to say that she was witness to Eren’s conversation with Zeke, where he theorized that Mikasa’s devotion to him had to be ingenuine. On the contrary, Ymir also bore witness to his lie when he rejected Mikasa.
But in the end, Mikasa and Eren’s love was mutual. Her devotion to him all her life was real, and so, because she loved him, she struck the final blow, ending the Rumbling. Those who truly love you will not enable your wrongdoings, they will try to stop you from going down the wrong path. Mikasa didn’t want to kill him, but seeing how far he had gone, and the fact that he was suffering, she ended his life. Ymir, in life, was suffering and wanted to live and love her daughters, but she couldn’t bring herself to let King Fritz die because she had such a reliance on him.
This is proven in a flashback with Ymir holding her daughters, had she let the spear hit him. Though when she let herself die, she wanted out of her misery, a small part of her remained in chains. This is something many women go through in real life, when in an abusive relationship. Because they’re so isolated and only with one person, they begin to develop an attachment, almost like they’re “in love”. Even after escaping, many of them are still unsure of their feelings and will even vouch on their abuser’s behalf.

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Second Chances and Gratitude
Mikasa saved the soul of Ymir as a child, but she also saved the soul of her as a mother. Ymir died as an adult and maintained the body and mentality of a child, as she never had the opportunity to grow up properly. As she grew with Mikasa and learned from her, she was able to heal her inner child. But it wasn’t just that, Ymir’s other dilemma was that she couldn’t be there for her children as a mother. She never received a true “thanks” or gratitude for her actions in life. Yet Mikasa addressed Ymir directly, thanking her for the lives she gave birth to. If it weren’t for her, Mikasa wouldn’t have been born or been able to fall in love. This gave Ymir closure, she found her answer and she realized her life did not exist in vain.
However, while Mikasa played a dominant role in her achieving freedom, Eren and even Armin inspired her as well. Eren held Ymir, reminding her of her own agency of the fact that she was her own person, letting her release the anger she held for years to experience what it means to be selfish, to harm others. Armin, through his conversation with Zeke, showed her that there is a balance to life. Every life has meaning, but it’s up to the individual how they go about it. Through the actions of the three, Ymir was essentially able to grow up and experience life, even if it was through extremes.
Just like Mikasa was her own person and made both selfless and selfish decisions throughout her life, Ymir was too – and that was the answer that allowed her to move on. If you consider it canon, given how Ymir takes the form of a butterfly, it can be concluded that she is the one who reunited both Eren and Mikasa in the afterlife in Itterashai.