Like many WataMote characters, Kayo starts as a background character who slowly gains a greater role. For much of the series until Chapter 152, Kayo exists as an unnamed friend of Uchi. She reveals in Chapter 106 that Uchi frequently talks about "a girl" when she points out Tomoko as "that girl you keep talking about" who is talking to "a guy" who turns out to be Tomoki.
Her name is revealed in Chapter 152 when Miyazaki indicates that she wishes to apologize to Uchi. Previously, Uchi has a temper-tantrum over their failure to reach the next round in the tennis table intramurals so she can face Tomoko, and Kayo unloads on Uchi about how she and the rest of Uchi's friends have noticed she is often absent and spending a great deal of time in Class 3-5. Later, when they find Uchi with Tomoko, she apologizes to her, and Uchi apologizes for her tantrum as well. Tomoko decides to deny that Uchi and her are friends and insults Uchi figuring that by directing all hate towards herself, Uchi and "the Emoji Group" will reconcile. When Uchi runs away crying, Kayo and the rest then question Tomoko about her relationship with Uchi. Kayo is initially reticent to the Girl with Glasses' suggestion that Uchi "likes" Tomoko, but when she deduces that Tomoko insulted Uchi in order to separate herself from Uchi and allow Uchi and the rest of them to reconcile against her, Kayo confronts Tomoko and encourages her to become a "close friend" to Uchi. Later, she sternly lectures Uchi to apologize to Tomoko.
Kayo does not reveal much of a separate personality until she confronts Uchi regarding her behavior towards her and their friends in Chapter 152. She proves direct and honest, but later apologizes to Uchi for not understanding that Uchi has had personal matters which have affected her. Her directness carries over to Tomoko when she immediately realizes Tomoko's "game" to insult Uchi in order to have Uchi's friends reconcile with Uchi against her, and while she confronts Tomoko, she supports her becoming a friend to Uchi. She later lectures Uchi about apologizing to Tomoko. This all suggess that Kayo can be frank, but caring, and insightful. While she seems initially reticent to accept that Uchi has a crush on a girl, she urges the both of them to apologize to one another.
Kayo is most notable for being drawn with wide and colorless pupils. She has long black hair with bangs. She has yet to appear in a color panel. As the Gallery demonstrates, she stands slightly shorter than Uchi's but taller than Tomoko.
- Volume 7: Chapters 59
- Volume 8: Chapters 77
- Volume 9: Chapters 79, 80, 82
- Volume 10: Chapter 93
- Volume 11: Chapters 105, 106, 107
- Volume 12: Chapters 112, 114, 117, 120, 122
- Volume 13: Chapters 123, 128, 129, 130.5, 131, Omake
- Volume 14: Chapters 134, 140
- Volume 15: Chapters 146, 152, 156,
- Volume 17: Chapters 161, 162, 163, 165
- Volume 18: Chapters 171, 172, 174, 175-1, 175-2, Omake
Strikethrough episodes or chapters indicate the character was mentioned but did not make a physical appearance)
Until Tomoko and Uchi mutually insult one another in Chapter 152, Kayo does not appear to have much, if any, relationship with Tomoko. That chapter reveals that she has come to feel that Uchi does not wish to hang out with her or their other friends since she spends her time visiting another classroom. When she and the rest seek out Uchi to apologize, they find her with Tomoko. Tomoko had learned that Uchi and her friends had a fight, and she purposely insults Uchi with intention to have Uchi's friends reconcile with Uchi against her. However, Kayo recognizes Tomoko act when Tomoko acknowledges this, Kayo takes part in a discussion with the rest in which they come to understand that the person whom Uchi had indicated she "liked," and the girl she has talked about, is Tomoko. Initially, Kayo protests that "Tomoko's a girl," but she makes no further objections. When she and the rest of her friends call Uchi back, and Tomoko apologizes to Uchi, they let her know that they understand that Uchi simply wants to be a "close friend" with Tomoko. Uchi panics and tries to pretend that she merely finds Tomoko hilariously fascinating as a "creep" (キモい).
Some days after this incident, Kayo, sternly asks Uchi if she has apologized to Tomoko. When Uchi mutters that she has not, Kayo lectures her that anyone would be insulted by being called "creepy/disgusting."
field trip and becomes separated from them during a trip to a famous amusement park. They all notice that Uchi talks a lot about "that girl," Tomoko. Other than Miyazaki, they are:
- Nagi (凪): Girl with Glasses: who has her hair, which is drawn between colorless and black in the manga, in a pony tail.
- Kaede (楓): Girl with Long Braid:
- Natsu (ナツ): Girl with Light Short Hair:in Chapter 129 she is absent from the group and the Girl with Glasses states that "Natsu ditched us to go with her boyfriend." Previously, the Girl with Glasses teased Natsu about being with a "Kazuki."
Chapter 152 reveals that she and the rest have felt abandoned by Uchi who keeps slipping away from them. Kayo directly confronts Uchi with this. When Girl with Glasses appears to understand that Uchi has a crush on Tomoko, Kayo initially protests that Tomoko "is a girl," but then urges Tomoko to be friends with Uchi.
Kayo thus far is the one who gets Uchi the closest to confess the nature of her crush for Tomoko. In Chapter 163, Kayo directly asks Uchi if the passing Tomoki makes her heart "pound." Uchi stares at him then declares that there is no キモい and no potential for there to be キモい in him, which reveals what she means by キモい.
- "A Girl has a Name": For much of her existence she has no name, and WataMote Wiki referred to her as the "Girl with Black Hair." Chapter 152 reveals her name as "Kayo" in the hiragana.
- "You even ditched us a bunch during the class trip too!" – confronting Uchi
- "No . . . she likes . . . Kuroki-san's a girl!"
- "There's six girls here, yet we're talking about pubic hair."
|Female Characters||Tomoko Kuroki | Shiki Futaki | Anna Haruna | Shizuku Hirasawa | Akari Iguchi | Hikari Itō | Megumi Imae | Asuka Katō | Kayo | Kotomi Komiyama | Mrs. Kuroki | Koharu Minami | Miyazaki | Nagi | Miho Narita | Yū Naruse | Hina Nemoto | Ogino | Akane Okada | Reina | Fūka Sasaki | Kiko Satozaki | Sayaka | Yuri Tamura | Mako Tanaka | Emiri Uchi | Masaki Yoshida|
|Male Characters||Tomoki Kuroki | Aomatsu | Art Teacher | Hatsushiba | Homeroom Teacher | Jun Ishimine | Kakinuma | Yoshinori Kiyota | Kosaka | Mr. Kuroki | Suzuki | Nico Tanigawa | Wada | Yocchan|
|Minor and Unnamed||Minor and Unnamed Recurring Characters|
|Manga Volumes||1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18|
|Anime Episodes||1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | OVA|