Starting Over: Regrets and Redemption in Reincarnation Isekai Anime

Love them or hate them, isekai are popular, the reincarnation variety especially, since the anime debut of Mushoku Tensei and Truck-kun. Within isekai's ubiquity, a niche within reincarnation isekai has caught my attention, represented through stories like Ascendance of a Bookworm and Re:Zero – Starting Life in Another World. These reincarnation isekai approach reincarnation less like a neat gimmick to be used however authors wish… and more like the tragic cycle Buddhism always regarded it to be.

Informed by Japan's heavily Buddhist culture, reincarnation isekai are uniquely positioned to tell stories of regret and redemption, and I intend to explain how. But first, let's discuss isekai and reincarnation.

For me, an isekai story is any narrative centered around protagonists who are transported into different worlds (or isekai worlds) and spend most of their time there. Those isekai worlds can exist in the past, persist alongside the original world, and consist of ones that humans previously crafted. Isekai worlds can't be ones that already exist in real-world religions and mythologies (like Valhalla, Heaven, Hades, and Jigoku). Those worlds also can't exist between or as part of the original world but are otherwise unobservable without certain abilities or qualifications (like in Yu-Yu Hakusho and The Ancient Magus' Bride).

The aforementioned definition is pretty broad and can encompass Western stories like A Connecticut Yankee in King Arthur's Court, and antecedents to isekai in Japan can be found in the folktale Urashima Taro (more details in this ANN article about Frieren and folktales). For modern Japanese isekai though, earlier works include InuYasha, Magic Knight Rayearth, The Vision of Escaflowne, and Digimon Adventure. As mentioned in this ANN article, The Familiar of Zero inspired several later famous isekai writers (especially those on Shousetsuka ni Naro), and Sword Art Online firmly established isekai as a popular genre and household name.

While isekai stories can be categorized by their settings (i.e., historical worlds, virtual game worlds, vague-European-with-some-Japanese-elements parallel fantasy worlds), I instead intend to classify them by how their protagonists are transported.

Transfer isekai have protagonists physically or mentally portaled into their isekai worlds. For example, InuYasha's Kagome is dragged down a well into medieval Japan by a demon; Log Horizon's player adventurers are marooned inside an MMO by a strange event; Rising of the Shield Hero's Naofumi is summoned into his fantastical world as a hero to face a larger threat, and Grimgar of Fantasy and Ash's isekai'd characters are popped into their fantastical world for no apparent reason. As a special mention, reverse-isekai, such as Re:CREATORS and Devil is a Part-Timer! flip who gets stranded, with the fantastical characters being stuck in the modern world.

While some transfer isekai strand characters in their isekai worlds indefinitely or permanently, reincarnation isekai do so by having them die in their original one first (i.e., get run over by Truck-kun). In addition to Mushoku Tensei, reincarnation isekai works include That Time I Got Reincarnated as a Slime (Slime Isekai), So I'm a Spider, So What?, My Next Life as a Villainess: All Routes Lead to Doom!, The Saga of Tanya the Evil, KonoSuba – God’s blessing on this wonderful world!!, Overlord, and Ascendance of a Bookworm. Re:Zero is debatably more a transfer isekai based on how its protagonist made it over, but I'm going to argue later that Re:Zero is a special enough case to count as a reincarnation one, too.

By its base definition, reincarnation is the rebirth of a person in a new body after death. Reincarnation beliefs were widespread among religions developed out of India. Of all these reincarnation religions, Buddhism succeeded at achieving the largest spread in communities outside of India, spreading throughout much of Asia, including Japan. Highly syncretic, Buddhism co-existed with (and co-opted) Japan's native animistic Shinto beliefs, eventually turning most Japanese (Shinto-)Buddhist. Buddhist beliefs and cosmology deeply influence Japanese culture, introducing the concept of reincarnation to the Japanese and the specific Buddhist understanding of it.

Japan being culturally Buddhist helps explain its history for writing stories with reincarnation, including anime and manga. Some authors stop at first base and prefer telling reincarnation stories without the more significant Buddhist subtext. Drawing from Japanese postmodernist Hiroki Azuma's Otaku: Japan's Database Animals, these authors engage in a database-ification process with reincarnation, freeing a trope from its history to be used however one wishes.

For example, take Evangelion and its prolific use of Christian imagery and jargon, which initially generated speculation and controversy over the story making a possible statement on Christianity. Evangelion's creators thought otherwise, stating they were just cool aesthetic elements. Quite ironically, Evangelion's Asuka, one of anime's most famous examples of the tsundere trope, is also affected by database-ification. While Asuka's irritable but vulnerable personality is tied to her severe abandonment issues, many tsundere characters since ignore the trope's association with mental baggage in favor of focusing on their quirkiness for the sake of desirability.

For reincarnation isekai, Slime Isekai matches the database-ification mold. Its protagonist, Rimuru, was a fairly unremarkable salaryman who gets randomly knifed to death and then reincarnated into an isekai world as a slime. The show then focuses mostly on Rimuru becoming ridiculously overpowered while building a great multi-racial polity. There isn't anything particularly Buddhist about the Slime Isekai author's use of reincarnation. It's just a means to turn a Japanese salary worker into an ability-busted slime and make his isekai world a playground sandbox.

Call it shallow or freeing, database-ification allows authors the headspace to craft more kinds of stories than otherwise with Christianity, tsundere, and reincarnation. Despite this freedom, specific stories can only be told through a closer connection with a given topic's roots. What are reincarnation's Buddhist origins? Rather than being a one-and-done occurrence, reincarnation for Buddhism is part of a perpetual cycle of death, rebirth, and suffering. Reincarnation in Buddhism isn't liberating; it's suffering.

I go more into the topic in an ANN article on Buddhism in Dororo, but in a nutshell, reincarnation for Buddhists is suffering because existence is suffering. While some folks may suffer more than others because they're reborn fortunate, everyone has the potential to suffer because existing leaves us vulnerable to experiencing it. Suffering is tied to attachments we develop towards things and people while we are alive. We suffer when the things and people we're attached to are lost to us. For instance, we misplace a precious item; we have a cherished possession stolen; we lose our youth; we are let down by an idea we believed in; we are betrayed by people we trusted; we lose our health; we are afraid to leave our loved ones alone; we agonize over losing our loved ones; we die, and we agonize over dying…

…over losing everything and everyone by dying.

We experience loss and regret.

And even once we die, there is no merciful oblivion or long quiet. We will exist again, and we will suffer again because we will be reborn again, and then we will die again, and we will exist again because we are subject to reincarnation, and reincarnation is a cycle. Ultimately, being reincarnated isn't an escape.

Reincarnation is a trap.

But it is also an opportunity.

Reincarnation is an opportunity to be better in the next life than in the previous one, to make choices that avoid the suffering one's past choices caused. It's that broader Japanese cultural belief in reincarnation's promise for redemption from regrets that leads some anime and manga to bookend relationship tragedies at one life's end, hoping to meet again and re-do things.

Meeting anew to re-do moments is a framing that suggests starting a new life with a clean slate or a reset chessboard; however, reincarnation in Buddhism is more nuanced than that because of karma. Since the term came into vogue among English speakers, karma has been popularly understood as actions in life causing similar reactions later on.

S-ranked criminals or the lazy jerkface at the office receiving their comeuppance is bad karma catching up with them, and benevolent heroes and the kind, competent lady at work receiving their just dues is good karma rewarding them. The Buddhist understanding of karma goes further by having it affect not only one life, but subsequent lives too.

Karma affects whether one is reborn sick, poor, and in an abusive household or healthy, wealthy, and into a loving family. The circumstances of birth do have a profound influence on the life a person ends up following. Karma isn't determinative, though, as one can earn good or bad karma and be reborn in better or worse circumstances, no matter the current station.

On top of karma, being reborn in Buddhism means not only leaving behind your old body, but also your past memories. Like being denied a cheat sheet for a test, you can imagine how not recalling your past lives' mistakes makes it more difficult for you to avoid making them again. Then again, something that looks like a curse might be a blessing, as forgetting past memories includes old prejudices that lead us to make those same errors anyway.

It's possible in Buddhism to unlock memories of all your past lives, but that only happens when you're "ready," which only happens when you've reached "enlightenment."

While acquiring good karma is better than obtaining bad karma in the context of rebirths, continuing to reincarnate means continuing to suffer, even if suffering is objectively less severe in good karma lives over bad ones. Buddhism professes that there is a way out of the reincarnation-suffering cycle, "enlightenment," which, to oversimplify a bit, is attained through a reckoning with our regrets from the attachments we obsess over.

To close the article, let's look at a couple of examples of reincarnation stories before examining two reincarnation isekai ones. They all take some liberties around the mechanics of Buddhist reincarnation, but still do a good job of touching on Buddhist themes of regret and redemption.

Satoshi Mizukami's Spirit Circle is the reincarnation story of a schoolboy named Futa Okeya, who is confronted by a girl transferring into his school. The girl, Koko Ishigami, declares her vengeance against him, a declaration he's confused by since it's the first time in this life he's met her. Her revenge is based on suffering he's caused her in his past lives, and she's been seeking him out ever since her current reincarnation suddenly remembered her lives. Futa begins remembering several of his past lives with Koko, too, including where he has hated her just as much for the suffering her past lives caused him. Despite being forced to re-witness his past lives by Koko, present-day Futa can't bring himself to hate Koko like before. Throughout learning more about present-day Futa, current reincarnation Koko can't bring herself to continue hating Futa now.

They end up developing feelings for each other, and by the story's end, they forgive each other's past lives. Once trapped by the suffering induced by their past resentments and the reincarnation cycle, they take a measured look at their pasts. They look at their regrets, decide they don't have to make the same decisions that caused their past lives so much pain, and agree that this reincarnated life is a good opportunity to start over with each other.

Aka Akasaka and Mengo Yokoyari's Oshi no Ko is the reincarnation story of Aqua Hoshino, who develops a close relationship with one of his terminally ill female child patients in his past life as doctor Amamiya Goro. She is obsessed with a particular idol, and while keeping her company, he becomes a fan like her. She sadly passes away, and he receives a new patient, the very same idol, Ai. That same idol is also very pregnant with twins, and he swears to deliver her babies successfully while keeping her children a secret. He then gets murdered by another fan who's disgusted she was in a relationship as an idol, and reincarnates with all his memories as the male twin Aqua. He lives an interesting but otherwise peaceful life as a weird-talking baby until that same toxic fan returns to stab his idol mother to death outside her apartment door. The stars in her eyes became void as he helplessly watched.

Realizing that there was another also responsible for the murder, someone connected to Ai's field of work, Aqua regrets letting it happen and swears vengeance. Throughout his efforts of breaking into entertainment to hunt the man who destroyed his idol, Aqua strains his conscience and his relationships, causing himself and everyone who cares for him to suffer. Tempted by the opportunity to let his hatred go and start over, as of the writing of this article, Aqua's still out for revenge and suffering for it.

Miya Kazuki's Ascendance of a Bookworm is the reincarnation isekai of a book-obsessed woman in modern Japan who, in poetic irony, gets sent to her medieval fantasy world by being literally buried by books. Having spent her past life also figuratively buried in them – minimizing her time with people so she can maximize her time reading – she's reborn as an illiterate girl to a poor family. She's reincarnated in a world where books are expensive because they are written by hand, and in a body so sickly, she has no choice but to depend on others to live instead of ignoring them. The girl, now Myne, views her new circumstances as the worst, as if her new world is punishing her specifically.

Her isekai world punishes her, but it's also trying to teach. As soon as Myne resolves to continue living and make her own books by working with others, she ends up growing to value and care for the people supporting her health and dreams, her new friends and family, in a way she never did in her past life of privilege. Prioritizing books over all else causes suffering to those who love her. As soon as she grows empathetic enough to love them just as much, she discovers that suffering is something she can't bear to cause them anymore. In a sequence that allows her to recall memories of her Japanese mother, she is filled with immense gratitude for her mom putting up with her selfishness…

…and tearful regret she didn't fully appreciate her sooner. She resolves not to repeat the same mistake with this new opportunity to start over.

Tappei Nagatsuki's Re:Zero – Starting Life in Another World's protagonist Subaru Natsuki is technically summoned into the world, but I think his "Return by Death" qualifies as a sort of reincarnation.

Re:Zero is the story of a boy from modern Japan who finds himself in a world seemingly straight from his otaku fantasies, complete with a kindly silver-haired half-elf heroine that's totally his type, and he's convinced himself he has to help. Other isekai stories might give someone in Subaru's position some special intelligence or ability to rise to the challenge after some initial struggle. Re:Zero hands Subaru "Return by Death," a power that returns or "reincarnates" him back to a fixed moment in the past after death to re-do decisions. It sounds convenient until he notices dying hurts a lot, and Re:Zero's isekai world makes it a point that people can die there easily and in ruthless ways.

Combined with not being especially strong or bright compared to many of Re:Zero's other isekai denizens, Subaru suffers excruciating failure and death, repeatedly. He survives his initial ordeals leveraging key insights he gleans from his death runs, which more-than-coincidentally requires him to seek the aid of others. He makes friends with silver-haired half-elf Emilia as well as others like her blue-haired oni-maid Rem. And then he runs into more ordeals more brutal than the last, which brutalize not only him but also the people he's grown to care about, repeatedly. Over and over.

Subaru reaches an emotional breaking point, and he admits to Rem his demons, the wretched feelings he's been trying to hide and compensate for all along until he couldn't anymore: he's weak, pathetic, and a loser. In his past life, he was a shut-in who was so afraid of enduring other people's judgments of his inadequacies that he stopped going to school and hid away in his parents' house. He saw his abrupt transfer into the isekai world as his chance to escape the suffering of his past choices scot-free, only for the world to punish him so hard for his hubris that he can't help but be reminded again.

His past sins, his bad karma, is catching up with him.

He loathes himself like he loathed himself then.

He admits he hates himself to Rem.

She agrees that, yes, Subaru is pathetic and weak (she's observed as much herself). However, he is not a loser; quitting doesn't suit the Subaru she's watched all this time. If Subaru was the loser he claims to be, he wouldn't have risked so much and gone to such lengths to save her. It's in his determination to save Rem in one ordeal despite the odds (and the fact she murdered him before in those loops) that she knows how he doesn't want to quit willingly, even if things get difficult. It's in his efforts to understand Rem in his past death loops and cheer her up at her lowest point (despite suspecting him enough to attack him previously) that she knows how kind and forgiving he is. He came in at the right time to save her life and said the right things to break her out of her self-hatred. She knows he's seeking redemption for his regrets, like she does for her own, so she knows he doesn't want to resign himself as a loser. It's this deeply understanding man she loves that she won't let him give into despair. She'll listen, comfort, and support him like he's done for her. Then she'll tell him to stand up again because the Subaru Natsuki that her love wants him to be isn't a quitter. He is a hero, her hero.

Having fallen into the lowest mental pits he's ever been, Rem tells Subaru to "Start over from zero." Through her words, he finally starts the journey of reckoning with the regrets of his past life, learning to like himself more, and eventually relying on his "Return by Death" less.

For, after all, reincarnation is an opportunity, but it is also suffering.

Social Scientist & History Buff. Dabbles in Creative Writing and anime criticism. Consider checking out his blog, Therefore It Is.