Otaku Terms Dictionary
From anime lingo and internet slang to modern Japanese expressions. Explore the words you'll encounter in otaku culture and everyday Japan.
Internet
15 terms
Chunibyo
厨二病(ちゅうにびょう)
Chunibyo (Chūnibyō / 厨二病) is Japanese slang for the cringeworthy, self-important phase that many teenagers go through around 8th grade. The name literally means “middle school second-year syndrome.” The 病 (byō, “disease”) part is tongue-in-cheek; it frames the awkward posturing of adolescence as something you “catch” or “come down with,” not an actual medical condition. The stereotype most people picture is the fantasy-delusion type: a teenager convinced they harbor a sealed supernatural power, a cursed eye, or a secret organization on their trail. But the term originally covered a much broader range of adolescent cringe, from trying too hard to seem mature to loudly rejecting anything mainstream. It works equally well as self-deprecating humor about your own embarrassing past or as a lighthearted jab at someone else, regardless of age. Chunibyo characters have become an established genre in anime and light novels, making the term widely recognized among overseas fans as well.
Coupling
カップリング(かっぷりんぐ)
Coupling (カップリング, kappuringu) is a word used in doujin and fan culture for the pairing of two characters in a romantic relationship. It means roughly what English-speaking fans call shipping. It applies to BL, which depicts romance between men, and to yuri (百合), which depicts romance between women. Male-female pairings work the same way. Shortened, it is written kapu (カプ) or CP. CP is widely used as a shared term among fans across East Asia, particularly in Chinese-speaking communities. An oshi-kapu (推しカプ) is a coupling you personally love and root for. On social media, people use it like "So-and-so and so-and-so are my oshi-kapu." A pairing that the original work presents as a couple is called an official coupling. The word coupling itself is not limited to unofficial interpretations. Even so, what sits at the center of fan activity is the fun of imagining and interpreting pairings that the original never shows. There are spin-off labels too. Pairing a character with themselves is called nijō (二乗), meaning "squared." A bond of friendship or partnership rather than romance is called konbi (コンビ), and to keep it apart from a romantic A×B, it is written A+B or A&B.
Kaigai Niki
海外ニキ(かいがいにき)
An internet slang term short for "kaigai no aniki" (overseas bros), used to affectionately refer to foreign users on the Japanese internet. Primarily used on Niconico, YouTube streams, and social media to refer to foreign men. It is also used regardless of gender, such as when referring to a group collectively. When specifically referring to women, "kaigai neki" is used instead.
Kusa
草(くさ)
A Japanese internet slang expression meaning laughter. Used to express amusement or that something is funny, much like "lol" in English. It can appear on its own at the end of a sentence, or in verb forms such as "kusa haeru" (grass is growing) and "kusa haeta" (grass grew). Translated literally, kusa simply means "grass," which makes absolutely no sense without knowing the context.
Narou Kei
なろう系(なろうけい)
A collective term for works originating from the web novel platform "Shousetsuka ni Narou" (Let's Become a Novelist), or more broadly, works that share the formulaic plot structures and settings commonly found there. These works typically follow specific patterns such as isekai (other world) reincarnation or transportation, overpowered cheat-like abilities, RPG-style status screens displaying skills, and harem dynamics. The label is not limited to works actually published on "Shousetsuka ni Narou"; it is also widely applied to light novels, anime, and manga with similar structural elements.
Nui
ぬい(ぬい)
Nui is short for nuigurumi (a plush toy or stuffed animal). It usually refers to plushies modeled after characters from anime, games, or idol groups. The term spread through otaku culture and social media, and it isn't limited to your own oshi (the character or idol someone is a fan of). Any character plushie might casually get called a nui. While it covers character plushies in general, in the context of oshikatsu (fan activities devoted to one's oshi) it leans toward meaning a plushie that makes your oshi three-dimensional, whether that oshi is a character, an idol, a VTuber, or someone else. It isn't only the official nui sold by makers or rights holders; it also includes self-made nui that fans sew from fabric, as well as store-bought plushies adopted as stand-ins for an oshi. Small, portable sizes are preferred, and people tend to pick ones meant to be carried along in a bag or held in hand. Keeping an oshi's nui close and taking it out to carry around, photograph, or dress up is a type of activity called nui-katsu. The closest English word is plushie, but the nuance differs slightly. Plushie refers to plush toys in general and doesn't carry the link to a particular character or oshi. Merch overlaps in the sense of official goods, yet it loses the side of nui that fans make themselves or carry around as a stand-in for someone.
Nui-katsu
ぬい活(ぬいかつ)
Nui-katsu refers to activities centered on plush toys. It covers everything you might do with a favorite plush or a plush of your oshi (nui), from collecting them and taking them out with you to photographing them and dressing them up. People often describe it as a branch of oshikatsu, the activities fans do for their oshi, but having a particular oshi is not a requirement. Heading out with a plush you fell for at first sight, or one you have kept close for years, and changing its outfits counts as nui katsu just the same. There are many ways to enjoy it. Beyond displaying a plush you have brought home, people carry them along to cafes and on trips to photograph them, which is called nui-dori, and dress them in outfits made for plush toys, known as nui-fuku. Several of these related activities have spread, each with its own term. Getting a new nui is called omukae (roughly to ‘bring home’), and the appeal lies more in enjoying living and going out together than just collecting them. There is no official standard and the names vary, but plushes around 20 cm tend to be used for display, while ones around 10 cm or 15 cm are easier to carry around. Outfits for changing clothes are also easy to find in the latter two sizes.
Yume
夢(ゆめ)
In otaku contexts, yume ("dream") is an umbrella term for a genre of fan works that depict a relationship between a character from an anime, manga, or game and either the reader themselves or an original character the reader has in mind. For novels it's called yume shousetsu, in illustration yume-e, and in comics yume manga, with the whole category referred to collectively as yume-muke. The original character who stands as the protagonist is the yumenushi, also read yumeshu. Some are self-insert figures the writer or reader maps themselves onto, others are built as a third party kept separate from the author, and there is no fixed template for their appearance or personality. In the narrow sense the word means a story in which the reader can freely replace the protagonist's name. This name conversion mechanism is where the genre began, and many posting sites still support it. People who enjoy yume are called yumejoshi, or yumedanshi for men. Yumejo is also in use, as is dorīmā, from the English word "dreamer". Yume in English-Speaking Fandom The closest concepts in English are self-insert and reader-insert, alongside the widely used Y/N (Your Name) placeholder that stands in for the reader's name. In recent years yume and yumeship have joined them as loanwords, and both are now understood as terms for the relationship between a character and the reader.
Yumejoshi
夢女子(ゆめじょし)
Yumejoshi are female fans who enjoy imagining a relationship between a character from an anime, manga, or game and themselves or a stand-in for themselves. The creative genre that turns this kind of imagining into fiction and illustration is yume, and the people who partake in it are called yumejoshi. The object of affection is usually a 2D character, though it can also be a real person, like an idol or a voice actor. The relationship is not only romantic. It covers friendship, bonds closer to family, and even a purely distant one, in which the fan never becomes directly involved and only watches over the character. Ways of entering the story vary just as widely: some fans identify with the protagonist directly, while others write them as a separate, independent character. At the center of the fan work is the yumenushi. This is the protagonist who appears in the story as a stand-in for the reader or the writer, most often an original character with no name. Through the yumenushi, the fan vicariously experiences time spent with a character on the other side of the screen. The word yume (dream) carries two senses at once: picturing a relationship that could not happen in reality, and stepping into the world of a story. In social media posts and in conversation, fans sometimes call themselves yume-onna, half in jest and at their own expense. The same written form can also be read yumejo.
