# What Is Isekai? Meaning, Origins, Types and Reverse Isekai Canonical: https://chapterchase.com/blog/what-is-isekai/ Read on ChapterChase: https://chapterchase.com/blog/what-is-isekai/ Author: ChapterChase Editorial Team Published: 2026-10-25 Updated: 2026-10-25 12:20:10 Categories: Reading Guides Tags: isekai, reverse isekai, light novels, anime, web novel genres Word count: 1340 > Isekai means 'another world': stories where a hero is transported to or reborn in a new world. Learn its origins, why trucks keep appearing, and reverse isekai. **Isekai** (Japanese for "another world") is a story in which an ordinary person is transported to, or reborn in, a different world, usually a fantasy one. The Oxford English Dictionary added the word in March 2024, defining it as a genre about a character "transported to or reincarnated in a different, strange, or unfamiliar world" ([Anime News Network, March 2024](https://www.animenewsnetwork.com/cms/.209348)). Isekai is now one of the biggest labels in anime, manga, light novels and web fiction. This guide explains the two main ways into another world, where the genre came from, why so many heroes are hit by trucks, the main subgenres including reverse isekai, and how to pick a first series. > **Key takeaways** > - An isekai hero either crosses into another world alive (transported) or dies and is reborn there (reincarnated). > - *Aura Battler Dunbine* (1983) is considered by many to be the first isekai anime. The modern boom grew from the web novel site Shōsetsuka ni Narō from late 2009. > - In 2024 isekai made up 15% of new TV anime: 34 new series, according to an Anime News Network analysis. > - Reverse isekai flips the premise: someone from a fantasy world ends up stranded in ours. > - The genre grew so crowded that some Japanese novel contests in 2016 and 2017 banned isekai entries outright. ### What does isekai mean? Isekai literally means "different world." In fiction it names a premise rather than a setting: the story starts in a familiar world, usually modern Japan, and moves its hero into an unfamiliar one. The OED notes the word is "frequently used as a modifier," as in isekai anime or an isekai light novel. There are two main routes in, and the OED's definition covers both: - **Transported.** The hero is pulled bodily into the other world, often summoned by a ritual or swallowed by a portal, and arrives as themselves. - **Reincarnated.** The hero dies in our world and is reborn in the other one, usually keeping their memories, sometimes as a baby, a monster or an object. Some stories add a third route: being trapped inside a virtual game. That variant overlaps with LitRPG, where the world runs on visible levels and stats. Our explainer on [what LitRPG is](https://chapterchase.com/blog/what-is-litrpg/) covers that overlap. ### Where did isekai come from? Portal stories are old, but the isekai label grew up in Japanese anime and web fiction. In Anime News Network's history of the genre, Miles Thomas Atherton writes that Yoshiyuki Tomino's *Aura Battler Dunbine* (1983) is "considered the first isekai anime by many," and he lists *Magic Knight Rayearth* and *The Vision of Escaflowne* among the "in another world" stories that came before the boom ([Anime News Network, January 2025](https://animenewsnetwork.com/feature/2025-01-22/the-state-of-isekai-anime/.219776)). The boom itself began online. Atherton dates the rise of the web novel platform Shōsetsuka ni Narō ("Let's Become a Novelist") to late 2009, with isekai as one of its early popular categories. The *Mushoku Tensei* web novel followed in 2012, and in mid-2016 *Re:Zero* and *KonoSuba* "popularized the term with overseas audiences." Some of these series moved from free web serials into published light novels, which our guide to [what a light novel is](https://chapterchase.com/blog/what-is-a-light-novel/) explains. ### How popular is isekai? Very, and still near its peak. Using data from MyAnimeList and White Box Entertainment, Atherton counted new isekai TV anime by year: 14 in 2019, 8 in 2020, 26 in 2021, 23 in 2022, 33 in 2023 and a peak of 34 in 2024, when the genre made up 15% of all new TV anime. He projected 32 for 2025. Source: Anime News Network (January 2025), using MyAnimeList and White Box Entertainment data. 2025 is a projection. The flood has produced pushback. In 2016, a light novel contest run by Bungaku Free Market and Shōsetsuka ni Narō banned entries about "traveling to alternate worlds" or "being reincarnated into other worlds," while in another contest 14 of 46 winners had "alternate world" in the title ([Anime News Network, July 2016](https://www.animenewsnetwork.com/interest/2016-07-08/light-novel-contest-overwhelmed-with-alternate-world-entries/.103996)). In 2017, a Kadokawa novel contest for adult readers said "any genre are OK [sic], except alternate world stories" ([SoraNews24, May 2017](https://soranews24.com/2017/05/22/anime-style-novel-contest-in-japan-bans-alternate-reality-stories-and-teen-protagonists/amp/)). ### Why do isekai heroes get hit by trucks? Because a sudden accident is the quickest way to kill off a modern hero and start the reincarnation. A fan-compiled chart reported by Anime News Network in 2018 counted causes of death among isekai protagonists: unknown causes led (102 works), then "traffic accident" (38 works) and "traffic accident by truck" (37 works), ahead of murder (31) and disease (24). The chart did not say which works it counted ([Anime News Network, January 2018](https://www.animenewsnetwork.com/interest/2018-01-12/traffic-accidents-top-list-of-causes-of-death-for-isekai-protagonists/.126275)). ### Types of isekai, including reverse isekai Definitions from the OED and Anime News Network; the grouping is ours. #### Reverse isekai Reverse isekai turns the premise around. Anime News Network defines it as a story "where a character from another world is trapped in the real world," with *The Devil Is a Part-Timer!* and *Otaku Elf* as examples. In our reading, the comedy comes from a demon lord or elf trying to cope with rent, convenience stores and smartphones. Atherton found it the least popular subgenre in his 2024 analysis. #### Villainess isekai Aimed at fans of otome (romance) games, this subgenre reincarnates the heroine "in the role not of the hero, but of the villainess" of a game she once played. Typically, her goal is to avoid the doom the game had planned for her character, as the title *All Routes Lead to Doom!* suggests. The best-known example is *My Next Life as a Villainess: All Routes Lead to Doom!* (2019). #### Trapped-in-a-game isekai Here the other world is a virtual one, as in *Sword Art Online*. Atherton notes that English-speaking fans began calling such stories isekai around the time of *Sword Art Online*, a use its author, Reki Kawahara, considered a misuse. ### Isekai in light novels and web novels Much of the genre starts in prose. Publishers Weekly reported in 2019 that light novels were attracting North American fans, with Yen Press the leading English publisher, and quoted One Peace Books' Robert McGuire: "there seems to be no stopping the isekai explosion" ([Publishers Weekly, July 2019](https://www.publishersweekly.com/pw/by-topic/booknews/comics/article/80607-mixing-prose-with-manga-light-novels-attract-north-american-fans.html)). Web serials remain a common starting point for new isekai. On ChapterChase, for example, you can read [The Hollowed Adventurer](https://chapterchase.com/novel/the-hollowed-adventurer/) (portal isekai), [Reincarnated as a God in a New World](https://chapterchase.com/novel/reincarnated-as-a-god-in-a-new-world/) (transmigration) and [Live In An Imperfect World](https://chapterchase.com/novel/live-in-an-imperfect-world-in-search-of-perfection/) (reincarnation). ### How to choose your first isekai - **Pick your route.** Want a fish-out-of-water adventurer? Choose transported. Want a second life with adult memories? Choose reincarnated. - **Check the tone in chapter one.** Isekai ranges from comedy and slow-life farming to grim survival, so read the opening before committing. - **Try the opposite.** If the premise feels tired, a reverse or villainess isekai keeps the setup but changes the jokes and stakes. - **Learn the vocabulary.** Terms like transmigration, regression and OP MC show up in tags. Our [web novel glossary](https://chapterchase.com/blog/web-novel-glossary-terms/) defines them, and our [genre guide](https://chapterchase.com/blog/web-novel-genres-explained/) shows how isekai fits next to cultivation and LitRPG. ### Frequently asked questions #### What does isekai mean in English? Literally "different world." In English it names the whole genre of heroes transported to or reincarnated in another world. #### What was the first isekai anime? *Aura Battler Dunbine* (1983) is considered the first by many, according to Anime News Network, though earlier portal stories exist. #### What is a reverse isekai? A story where someone from a fantasy world is stranded in ours, such as *The Devil Is a Part-Timer!* #### Is isekai the same as LitRPG? No. Isekai is about crossing into another world, while LitRPG is about visible game mechanics. Many stories are both, especially trapped-in-a-game isekai. ### The short version Isekai is the "another world" story: a modern person crosses over, by portal or by rebirth, and has to make a life there. It grew from 1980s anime and exploded through web novels in the 2010s, and it is now common enough to have its own dictionary entry, its own trope for trucks and its own backlash. Pick the route and tone you like, and the genre has plenty to offer.