The following data is intended as a companion to "The Imperialism of Isekai" and "The Gender Dynamics of Isekai." The data is drawn from 50 of the most popular isekai shows over the last forty years. The reader will notice that a disproportionate amount of these shows aired in the late 2010s. This is explained by the explosion in popularity of isekai during that period.
The year associated with each show is the year in which it first aired. In many cases, the shows are adapted from previous media. In these cases, the year that the anime aired is used. This is intended to be a sample of 50 isekai anime, and while the general trends it demonstrates are applicable to light novels, manga, etc., this data should not be misinterpreted as applying directly to those mediums.
List of Sampled Isekai Anime
| The Ambition of Oda Nobuna | Arifureta: From Commonplace to World's Strongest | Ascendance of a Bookworm | Death March to the Parallel World Rhapsody | Demon Lord, Retry! |
| Digimon Adventures | Do You Love Your Mom And Her Two-Hit Multi-Target Attacks? | El-Hazard | Endride | The Familiar of Zero |
| Fushigi Yūgi: The Mysterious Play | Gate | Grimgar of Fantasy and Ash | High School Prodigies Have It Easy Even In Another World | How Not to Summon a Demon Lord |
| In Another World with My Smartphone | Inuyasha | Isekai Cheat Magician | Knight's & Magic | KonoSuba |
| Kyo Kara Maoh! | Log Horizon | Magic Knight Rayearth | Magical Shopping Arcade Abenobashi | No Game No Life |
| Outbreak Company | Overlord | Problem Children Are Coming from Another World, Aren't They? | Re:Zero | The Rising of the Shield Hero |
| The Saga of Tanya the Evil | Tenchi Muyo! War on Geminar | That Time I Got Reincarnated as a Slime | Those Who Hunt Elves | The Twelve Kingdoms |
| The Vision of Escaflowne | Wise Man's Grandchild | Sword Art Online | Drifters | .hack//Sign |
| Btoom! | Restaurant to Another World | My Next Life as a Villainess: All Routes Lead to Doom! | Didn't I Say to Make My Abilities Average in the Next Life? | Dog Days |
| Spirited Away | Now and Then, Here and There | Aura Battler Dunbine | Mashin Hero Wataru | NG Knight Ramune & 40 |
Of the anime sampled, 2 aired in the 1980s, 8 aired in the 1990s, 8 aired in the 2000s, and 32 aired during the 2010s (My Next Life as a Villainess: All Routes Lead to Doom! technically aired early in 2020). These numbers represent a decent illustration of the popularity of isekai anime over the years.
Of the anime sampled, 3 involved the protagonist time traveling into the "other world." Even in these instances, the worlds into which they travel are highly fantastical.
The Saga of Tanya the Evil, Inuyasha, and The Ambition of Oda Nobuna
Of the anime sampled, 11 involved the protagonist being transported into a video game. These games are almost always RPGs (usually with an MMO flair) but can sometimes (when the protagonist is female) be otome games.
The protagonists in this type of isekai are almost always young men. Only when the game is explicitly labeled as an otome game are the protagonists female. Some of these games do, however, involve female characters being transported into RPG games (Sword Art Online, Log Horizon) but they are never the explicit protagonist. The only exception to this is Do You Love Your Mom and Her Two-Hit Multi-Target Attacks?, in which the young man's mother serves as a sort of protagonist.
Of the anime sampled, 36 involve the protagonist being transported into a fantasy world. It should be noted, however, that many of these fantasy worlds contain RPG elements. For example, while we counted KonoSuba as being a fantasy world, it is a fantasy world very much modeled after role-playing games.
Gender Breakdown
For the purpose of this investigation, we are interested in the person who is transported into the foreign world and the "natives" of that world.
Of the anime sampled, 34 feature a male protagonist being transported to the other world. Only 9 feature a female protagonist being transported to the other world. 7 feature both males and females of equal importance being transported.
The average age of the male being transported (before transportation) is 19.97 years old. The median age is 17.
The average age of the female being transported (before transportation) is 15.11. The median age is 15.
As one can see, the male median is a full 3 years below the average, while the female median equals almost exactly the female mean. The reason for this is because there are a few isekai that feature older men being transported, which pulls up the mean but not the median, while there are none that feature older women. The sole isekai in which an older woman is transported is Do You Love Your Mom and Her Two-Hit Multi-Target Attacks? However, this show does not feature a sole female protagonist, and thus it is not counted.
As for the "natives" of the world into which the protagonist is transported, we have taken to identifying the predominant gender of the most important native character/s. For example, the primary "native" character in The Familiar of Zero is Louise. Thus, that show is marked as native = female, with its native female having an age of 16. The "transported" in the same show, Saito, is marked as male, with an age of 17. The intention here is to identify broad trends, not hyper-accurately characterize individual shows.
Of the anime sampled, 32 had predominantly female natives, while 8 had predominantly male natives. The remaining 10 were unclear. A more detailed breakdown can be seen below:
Male protagonists with female natives: 26
Female protagonists with male natives: 5
Male protagonists with male natives: 3
Female protagonists with female natives: 1
Male protagonists with unclear natives: 5
Female protagonists with unclear natives: 3
Unclear protagonists with female natives: 5
Unclear protagonists with male natives: 0
The mean age of the male natives is 16, while the median age is also 16.
The mean age of the female natives is 15.19, while the median age is 15.
The mean age of female natives in isekai with male protagonists is 15.16.
Analysis
This data shows nothing surprising. The overwhelming presence of teenagers in isekai is confirmed. Both the transported protagonists and the natives are overwhelmingly teenagers. The males that are transported tend to be a few years older than the females that are transported. The spread of ages is also more constricted among the females, with practically all of them being teenagers. They will occasionally rise up into the 20s. With the males, while most are still teenagers, there is more room for men in their 20s and 30s. However, often these older men will find that, upon their transportation, they now occupy a younger body.
It should also come as no surprise that the beings in the "other world" that prove important to the transported protagonist are overwhelmingly teenage girls. In many of these instances, the girls will develop romantic feelings for the transported protagonist. The transported protagonist, as the data indicates, is usually a few years older than the girls, though in some cases he can be much older.
To add further confusion, there is an incessant trend of declaring that a girl who looks 15 and acts 15 is actually a 900 year old vampire wizard. It is also possible to have a girl who is technically a few years (or even a few weeks) old but looks and acts 15. In these instances, we have labeled them as the age they appear, or the age that other characters clearly perceive them to be.
For some further discussion on the moral difficulties inherent in this voodoo-aging nonsense, see "I Dated a Robot: The Ethics of Robot-Human Relations" by American Oneironautics.
Ultimately, this data draws one to the conclusion that isekai, as a general rule, features male protagonists being transported into fantasy lands in which they lord over females somewhat younger than themselves. While some isekai rejects this framework, the trends indicate that the genre, as a whole, leans towards this fundamental conceit.