Koiwai, Yotsuba

小岩井四葉

Yotsuba is depicted as a petite girl with green hair styled into four pigtails, which gives her a resemblance to her namesake, the four-leaf clover. She possesses a carefree and energetic personality, finding joy in simple things while learning about various aspects of daily life. In the Japanese version, Yotsuba's dialogue is written without kanji, appearing simpler and more childlike, and uses a typeface that conveys high intensity. Other characters, particularly members of the neighboring Ayase family, notice her energy. Her father comments on her carefree nature, saying, "She can find happiness in anything. Nothing in this world can get her down." However, she does cry when deeply frightened or upset, and she has an unexplained fear of anything resembling a bullseye.
At the beginning of the series, Yotsuba displays very little knowledge of the world around her, even for a young child. Items such as swings, doorbells, cicadas, and air conditioners fascinate and confuse her, though she is not disturbed by her ignorance. She occasionally mispronounces new words and creates neologisms, such as "Yotsubox" as a portmanteau of "Yotsuba's Box," and often repeats phrases spoken by adult characters in incongruous ways. Yotsuba is frequently shown drawing, although she is not as skilled an artist as she believes, and she is an excellent swimmer.
The series offers few details about her life prior to the start. She is an adopted child, and her birthplace is unknown to the reader, although she claims to be from an island "to the left." Koiwai, Yotsuba's adopted father, states that he met her as an orphan in a foreign country and, before he realized it, was raising her as his own; strangers sometimes mistake her for a foreigner. When asked about her mother, she does not understand the question, and she becomes confused by the concept of having two sets of grandparents. Before moving to her current home, Yotsuba lived in the countryside with Koiwai and his mother. She initially tells Fuka Ayase that she is six years old, but her father later corrects this, stating she is actually five years old.
Yotsuba has never attended school, and as of the first chapter, she does not know what a grade is. In chapter 35, she fails to understand repeated explanations of homework.