Yotsuba Koiwai

Yotsuba Koiwai is the titular main character from the Yotsuba&! manga.

Yostuba is a five year old girl that learns things every day. Yotsuba was abandoned by her mother. Her country of origin is unknown. The small information we have is she came from the left, meaning she could be mandarin. How Mr. Koiwai came to meet her is unknown, but he stated that he just started taking care of her and soon enough, became her (adoptive) father.

Appearance
Yotsuba is drawn as a small girl with green hair done in four pigtails, giving her somewhat the appearance of her namesake, a four-leaf clover. She also has matching green eyes, and is considered by most people to be very cute. Her standard outfit consists of a white T-shirt with light red sleeves (in the fall she wears the same shirt but with long sleeves), matching red and white shoes, and a pair of beige shorts.

Personality
Yotsuba has a carefree and energetic personality, taking delight in simple matters even as she learns about all manner of things in her daily life. In Japanese, Yotsuba's dialogue is written without kanji, making it seem simpler and more child-like, and in a typeface that gives the impression of speaking with high intensity. Her energy is noted by other characters, especially members of the neighboring Ayase family. However, when deeply frightened or upset, she does cry, and she has an unexplained fear of anything resembling a bullseye.

At the start of the series, Yotsuba is shown as having very little knowledge of the world around her, even for a young child. Things such as swings, doorbells, cicadas, and air conditioners all fascinate and confuse her, although she is not perturbed by her ignorance. She occasionally mispronounces new words and creates neologisms, such as "Yotsubox" as a portmanteau of "Yotsuba's Box", and often repeats, in incongruous ways, phrases spoken by adult characters around her. Yotsuba is frequently shown drawing, though she is not as good an artist as she thinks she is, and she is an excellent swimmer.

Trivia

 * The series provides few details about her life before its start. She is an adopted child, with her birthplace unknown to the reader, although she claims she's from an island "to the left." Koiwai, Yotsuba's adopted father, says he met her as an orphan in a foreign country and before he knew it he was raising her as his own; she is sometimes taken for a foreigner by strangers. When asked about her mother, she doesn't understand the question, and she gets confused by the concept of having two sets of grandparents.
 * Before moving to her current home, Yotsuba lived in the country with Koiwai and his mother. She initially claims to Fuuka Ayase she is six years old, but her father later corrects this, saying she is in fact five years old.
 * Yotsuba has never attended school, and as of the first chapter does not know what a grade is. In chapter 35, she fails to understand repeated explanations of homework.


 * The popular English-language imageboard 4chan, which is known in Japanese as "Yotsuba Channel", adopted Yotsuba Koiwai as an unofficial mascot: the site logo and icon at one point consisted of four leaves positioned identically to her distinctive four green pigtails, and she appears in the HTTP 404 message (leading to the nickname of "404 Girl"), banned user messages, banner ads, and logos. The software the site runs on is code-named Yotsuba.
 * In the Korean MMORPG MapleStory, Yotsuba's hairstyle can be obtained in a salon located in a town called Zipangu (an archaic name for Japan).
 * She appears on the ending part of the spin-off anime series Nyanbo!, based on the Danbo character that appears in two chapters of the Yotsuba&! manga.
 * In the anime series Eromanga Sensei, she is seen within the background alongside a Danbo.