If you watch My Hero Academia till season 4, then you probably have a lot of burning questions regarding one character in particular. It’s the adorable Eri-Chan whom I feel is the Nezuko of the My Hero Academia series. There’s a lot of mystery surrounding Eri with season 4 not revealing much about the character. Don’t worry, Senpai will explain the most frequent questions on Eri-Chan.

I will list down the questions that frequently come up so you can skip to whichever that interests you.

Eri’s backstory

Eri-Chan My Hero Academia

Eri is six years old in the anime and seven where things currently stand in the manga. She’s the granddaughter of the former boss of the Shie Hassakai who gets taken under the wing of Chisaki Kai also known as Overhaul. The former boss of the yakuza clan entrusts Eri to Chisaki because they have similar quirks, and hoped that he would help teach her how to control her powers.

Eri’s lack of control of her quirk led to the unintentional demise of her father after the latter touched her. Upon contact, her father immediately ceased to exist. The event causes Eri’s mother to send Eri-Chan to her grandfather and abandoning her own daughter.

Instead of helping her gain control, Chisaki abuses her abilities when he finds out that her powers can erase the quirk of others. Chisaki uses this to his advantage to fulfil his ideals by mass-producing a drug that can permanently remove a person’s quirk. By doing this, the yakuza can finally take a more centre stage like in the old days.

During the Shie Hassaikai’s arc, Deku and friends defeat Chisaki saving Eri in the process. Currently, she’s residing in UA where the higher-ups have agreed to take her in as it’s the safest place for her to be. She is learning how to control her powers there with the help of Eraser Head.

What is Eri’s quirk?

Eri-Chan My Hero Academia

Now, this is where things get confusing. Eri-Chan’s name is composed of two characters: “break” and “logic“. Put together, it would mean destruction, but I prefer identifying her as someone who breaks logic because of how her powers work. Eri-Chan didn’t inherit any of her parent’s quirk due to a mutation in her cells/chromosome that houses the genes of one’s quirk.

Eri’s quirk is Rewind, but it’s not as simple as it sounds. My understanding of her ability is that Eri can rewind a body’s ‘biological clock‘. It means that her quirk can do three things: restore a person’s health, make someone younger, and reverse the effects of evolution. Her powers only work on living things.

I believe that her quirk works on a cellular level and has nothing to do with time and space. I think a more appropriate name for her ability would be Reverse instead of Rewind. That’s just my opinion. The drugs that Chisaki creates proves that her blood targets the quirk chromosome of a person and completely erasing it in the process. My theory is that the way this works is due to her quirk being a mutation of the chromosome itself.

We see Eri use her quirk during Deku’s battle against Overhaul. With her touch, Deku can use One for All at 100% without worrying about the effects it has on his body as she neutralises it with her powers. My issue with this is that how does Deku know far he should go, or how much to push himself to negate the effects of Eri-Chan’s quirk. Eri has no control and Deku has no idea of the extent of her powers, but by the end of the fight, we see Deku maintain the injuries he had before the battle with Overhaul.

How did Deku estimate how much to destroy his body by using 100% of One for All? The injury on his arms that he got way back was still there. How did he manage to maintain the same amount of strength? Eri-Chan could have reversed the effects to when he could only use 5% of One for All instead of the current 8/20%. I know it sounds like I’m nitpicking, but these are the questions that will arise due to a power that lacks enough explanation from the author.

The powerful nature of Eri’s ability has something to do with Quirk Singularity Doomsday Theory. I’ll explain that below but because of this a limiting factor was introduced. Her quirk is an Accumulation type quirk similar to One for All. For Eri to be able to use her powers, she has to accumulate something in return. What is the accumulating factor? We still don’t know, but the more she accumulates this unknown thing, the larger her horn grows.

If Senpai had to guess, I think the accumulation factor has got to do with emotion. It’s still unknown in the manga, so I don’t want to make any wild speculations, but I’ll update once I have more information.

Quirk Singularity Doomsday Theory

Eri-Chan My Hero Academia

In the world of My Hero Academia, people who have quirks make up 80% of the population. When two quirk users have a child, their child would either inherit one of the powers, or a combination of the two. The theory states that as generations pass and quirks keep mixing and evolving, it will become too powerful for the wielder to bear. A perfect example would be Eri-Chan who would bring more harm than good if she uses her power. Imagine if Todoroki’s quirk mixed with Dark Shadow. I wonder what would happen?

Could Eri help Mirio regain his quirk?

Eri-Chan My Hero Academia

Theoretically speaking Eri would be able to rewind the effects of the drug that made Mirio quirkless. That is IF she learns to control her powers first. As of now, she’s under the direct supervision of Aizawa, but there’s still a long way to go. I do believe that they’re setting it up for her to be able to rewind the effects of the drug. Nighteye saw Mirio’s future and said that everything would be alright.

Could Eri heal All Might and help restore One for All?

Yes and no. Yes, Eri could heal All Might with her quirk by rewinding the state of his body to when he was healthy and had a stomach. As of now, that’s currently impossible as she lacks control as I said earlier. To heal All Might would be a harder feat than helping Mirio regain his quirk. Why? Because Eri would have to rewind the state of All Might’s body by decades to before his first fight against All for One where he got injured. Chisaki even said that she could rewind a person into being an ape because what she’s manipulating isn’t time, but genetics which is on a cellular level.

No, she can’t restore One for All in All Might that’s because he already passed it on to Deku. He never had a quirk, to begin with, so it was never in his genes. I don’t understand why people want this to happen anyway. If All Might had One for All, then there wouldn’t be any meaning in Deku’s journey towards becoming the strongest hero. The story isn’t about All Might, instead, it’s the story of the next generation. His loss as a hero is what lits the fire for the future.

Another issue I have with Eri’s quirk is that it can solve almost any problem. There wouldn’t be any real consequences because she could just rewind everything. Yes, you can argue that if you don’t use it then it doesn’t count, but since it’s there why not use it? It’s the more logical option to end suffering. People will say that we’re becoming like Overhaul and using her as a tool but wouldn’t she be happy if she could help the good guys? It would even make her a hero. All heroes in My Hero Academia in one way or another are tools.

If you’re curious on to which is All Might’s true form you can read my explanation here.

Is Eri-Chan related to Shigaraki Tomura?

Well, I get the resemblance, but no they aren’t related. Shigaraki is the grandson of Nana Shimura while Eri-Chan is the granddaughter of the former boss of the Shie Hassaikai. These are two different people. Among their similarities:

  • They both have white hair and red eyes
  • Both using their quirks to accidentally kill their own family member
  • Both are connected to organized crime and were taken in by the head of the organization

When I first watched the Shie Hassakai’s arc even I thought they were somehow related.

Is Eri immortal?

Another fan favourite theory is whether Eri-Chan immortal? Of course, the author wouldn’t allow it, but theoretically speaking yes she could be. If she grew old and lived till 80, she could always rewind her body to when she was younger hence forever prolonging her life. Two factors are preventing this from happening. One, she has no control and two we don’t know what she needs to accumulate for her to use her quirk. Until these two variables become fixed, then it’s up to Eri-Chan if she wants to live forever.

Of course who wouldn’t want Eri alive forever, but how lonely would that be?


Eri-Chan is the girl we would die protecting. It’s sad to say, but in My Hero Academia she has the most depressing backstory. She has watched the deaths of the people she cared for and has never known familial affection.

If there are any lingering questions regarding Eri-Chan, then do leave them in the comments. Let me know if there’s something you want me to write on, or if there’s anything that I got wrong. Anyway, thanks for reading.

Let’s protect that smile