Koiwai household

Koiwai household[edit]

Yotsuba Koiwai (小岩井 よつば Koiwai Yotsuba?) / "Yotsuba" (よつば Yotsuba?)

Main article: Yotsuba Koiwai

Yotsuba is depicted as an energetic five-year-old girl with a child's wonder towards even the most unremarkable of new discoveries. She is shown finding enjoyment in nearly everything, and her constant enthusiasm is infectious. Before moving to their present house, she and Koiwai used to reside with his mother, and before that on an island that is, according to Yotsuba, located "to the left". Almost nothing is known about her biological parentage other than that she was orphaned somewhere outside of Japan and subsequently adopted by Koiwai. Hence, she is often mistaken for a foreigner by people who meet her for the first time. Her excellent skills as a swimmer are admired and even envied by some of the adults. But she is not a gifted artist as she is made to believe; those childish sketches she draws are praised just to prevent hurt feelings.

The name "Yotsuba" (よつば?) can be translated as "four leaved clover," and is part of the phrase yotsuba no kurōbā (四葉のクローバー?, "four-leaf clover"). Her green hair is always styled into four pigtails (even during bedtime), giving her somewhat the appearance of her namesake.

Mr. Koiwai (小岩井 Koiwai?) / "Daddy" (とーちゃん tō-chan?)

Mr. Koiwai, (given name still not yet revealed) is Yotsuba's adoptive father. The circumstances which led towards her adoption are obscure and the fate of her birth parents/family is not even mentioned. When asked by Fuuka, he tells her that he found Yotsuba while visiting a foreign country then he just decided on adopting and taking the little girl along with him back to Japan; Mr. Koiwai provided no further details beyond that. Although he may be nonchalant in telling other people that Yotsuba is a weirdo, he can be very offbeat himself and has a tendency to behave in a plethora of unabashedly silly ways; 

Mr. Koiwai normally acts as such in order to lighten up the mood and/or when he is humorously emphasizing a point. He is depicted as a youthful dad with the carefree lifestyle of a slacker who habitually wears an undershirt coupled with a pair of boxer shorts since he is just at home most of the time; he often feels sorry for himself and is apologetic to other people who catches a rare glimpse of his "irresponsible" getup. The reason for this homebody way of life is due to the fact that Mr. Koiwai works in his house as a freelance translator, though the specific type of languages and/or materials he transcribes remains unknown. 

Every once in a while, he does get out of the house if it is required by his job or when doing errands such as grocery shopping; he would also gladly accept friendly invitations for outdoor activities and/or night-outs if his quite hectic schedule could allow it. He usually brings his little girl along in these trips which helps add a unique flavor to each encounters given the five-year-old's infallible eagerness and exuberance. 

Despite his laid-back personality and playful behavior, Koiwai does aim to be a good father and proper role model to Yotsuba; he will duly reprimand and chastise his child whenever she causes an unfavorable situation that definitely warrants a firmer disciplinary course of action.

Ayase household[edit]

A page from the manga. In the top panel, a dark-haired girl looks shocked. The next panel shows the same girl with a group of three other girls, and a middle-aged couple seated for breakfast. Each holds a piece of paper.

Above, Fuka reacts to shocking news being spread about her by Yotsuba. Below, from left to right: Fuka, Yotsuba, Asagi, Ena, Mrs. Ayase, and Mr. Ayase at breakfast.

The Ayases live next-door to the Koiwais.

Asagi Ayase (綾瀬 あさぎ Ayase Asagi?)

20-something years old and the eldest of the three Ayase sisters, Asagi lives at home while attending a nearby university. She is depicted as a very attractive young woman who enjoys creating mischief and teasing people, especially her parents; her friend Torako once described her as a horrible person for slyly manipulating Ena. She is the best of the Ayases at making use of Yotsuba's enthusiasm and naivety for her own personal amusement albeit without any malicious intent. 

Her mother claims Asagi was very much like Yotsuba when she was young. Mrs. Ayase ponders on how such a cute child could turn out to be a delinquent, much to her eldest daughter's annoyance. Asagi's irreverence may have come from her mother's teasing when she was a child. For example, in the past when Asagi presented Mrs. Ayase with a four-leaf clover, her mother mischievously asked for a five-leaf clover instead. Unable to locate one, young Asagi was reduced to tears. Yotsuba often refers to her as the "Pretty one".

Fuka Ayase (綾瀬 風香 Ayase Fūka?)

The middle Ayase sister, Fuka (also romanized as Fuuka) is 16 years old and in her second year at a local high school. She appears to be the most dependable and responsible of the sisters. Fuka is often called upon to purchase the groceries; she is knowledgeable and active in civic affairs within their community; and during Yotsuba's eventful first visit to her school, one student calls her "vice-president." Fuka usually finds herself frequently going out of her way to help out the Koiwais, even though she does not really intend to do so, which often devolve into embarrassingly awkward scenarios. 

Besides Jumbo, she has observed the Koiwais' eccentricities and oddball tendencies more than anyone else. Fuuka is often slightly ridiculed by the other characters in regards to her fashion taste and sense of humor; she is fond of making bad puns which irritates Asagi and she tends to wear t-shirts with odd or childish graphics (such as Chiyo's "father" from Azumanga Daioh, who also appears as a plushie in her room and as a keychain on her bag). Yotsuba earlier referred to her as "the one who is not pretty", much to Fuka's dismay.

Ena Ayase (綾瀬 恵那 Ayase Ena?)

The youngest Ayase sister, Ena is about 10 years old and enrolled in a nearby elementary school. Being the ones closest to Yotsuba's age, she and her best friend Miura are the titular character's most frequent playmates. Arguably the most genuinely kind and considerate member of the entire cast, Ena is generally well-liked by everyone she interacts with. Ecologically sensible despite her very young age, she tries to be environment-friendly by informing others about the negative effects of global warming (she limits her usage of air conditioning) and teaching Yotsuba the benefits of recycling. Appreciative, level-headed and smart, she behaves as an ideal big sister figure to Yotsuba. 

But her attempts to spare the five-year-old's fragile feelings sometimes lead her to make little white lies, such as praising Yotsuba's childish sketches or letting Yotsuba believe that her friend Miura (concealed in a cardboard costume) is a real robot named Cardbo (in ADV's translation) or Danbo (in Yen's translation) (ダンボー Danbō?), with repercussions that more often than not rebound on herself and Miura. During her free time, Ena often does sketches (she has very good drawing skills) and can be seen playing with her finely-dressed teddy bears, either by herself or with Yotsuba. Eager and willing to try out new experiences, Ena is unexpectedly not squeamish and even enthusiastic about such activities like handling large frogs and cleaning out live fish. Yotsuba once referred to her as the "small one".

Mrs. Ayase (綾瀬家の母 Ayase-ke no Haha?) / "Mommy" (かーちゃん kā-chan?)

The mother of the Ayase sisters. Mrs. Ayase seems to have aged quite well as she appears too young to be a mother of a twenty-year-old daughter. She frequently has Yotsuba over as a guest and even encourages the child to visit them every day. Yotsuba's overly-familiar habit of calling her "Mom" is due to her generosity (she is fond of giving Yotsuba treats because she likes to watch her eat) and uber-tolerant nature (she doesn't mind Yotsuba soaking her with a water pistol then acts dead to play the part). Nostalgia might be the primary reason for her endearment towards Yotsuba; she is able to relive and reminisce on Asagi's younger years (cuter and better days according to her) through the little girl. Asagi's pranks and vexatious behavior exasperates her constantly despite her husband's remark that mother and daughter have very similar personalities; an observation that both Mrs. 

Ayase and Asagi instantly deny at the same time. Having something akin to a sweet tooth, she has a fondness for ice creams, cakes, and other sugary desserts. These items are often regularly stocked in their fridge, a fact that Yotsuba always has in mind whenever she has her sights on such treats; cravings that prompt her to rush next door much to Mr. Koiwai's embarrassment and disapproval.

Mr. Ayase (綾瀬家の父 Ayase-ke no Chichi?)

The father of the three sisters and head of their household. Mr. Ayase is almost never seen at home, particularly during the regular workweek. While his profession is not yet revealed, it is comparable to the life pattern of a common salaryman. Asagi frequently teases him about his constant absences, even sometimes referring to him in the past tense as if he has died already. Still, Mr. Ayase is nonetheless on very good terms with his family; he is doted by Ena and is quite protective of Fuuka. Laid-back, congenial, optimistic, and sentimental; Mr. Ayase's personality is apparently inherited by his more agreeable children: Fuuka and Ena. Whenever he is at home during Yotsuba's visits, the little girl seems to be extra courteous towards him and appears to put on her best behavior even though Mr. Ayase has treated her like a member of the family ever since their first acquaintance.