Tamon's B-Side

An anime television series adaptation produced by J.C.Staff aired from January to March 2026.

Utage Kinoshita is an excitable high school student who supports Tamon Fukuhara, a wildly popular member of the idol group F/ACE. To Utage, Tamon is a flawless, radiant idol who gives her the motivation to get through daily life. Utage works as a part-time housekeeper, and is assigned a new client when a coworker gets sick. To her surprise, this new client is Tamon, and she quickly discovers that behind his perfect public image, he is deeply insecure, pessimistic, gloomy, and has no friends. As Utage becomes involved in Tamon's private life, she works to support him through his self-doubt and fear of failing his fans, while struggling to reconcile the contrast between his idol persona and his true self.

Utage Kinoshita (木下 うたげ, Kinoshita Utage) Voiced by: Maika Sasaki (voice drama), Saori Hayami (anime) (Japanese); Abigail Blythe (English) A 17-year-old high school girl and an avid fan of Tamon, Utage works part-time as a housekeeper for her oshikatsu. She was initially assigned to Tamon's house to cover the absence of her co-worker before officially hired as his housekeeper. She would do anything to keep Tamon retaining his idol job, including scolding him every-time Tamon says any negative remarks about himself or maintaining her distance with Tamon as a fan. One of the running gags is that she frequently drops her uchiwa and somebody else ends up picking it up for her. Hayami stated that Utage is expressive and sometimes out of control. However, deep down, she has a big heart and straight-forward personality, which makes her an adorable character. Tamon Fukuhara (福原 多聞, Fukuhara Tamon) Voiced by: Takuya Eguchi (voice drama), Kakeru Hatano (anime) (Japanese); Conner Allison (English) Portrayed by: Kanata Narabayashi The 18-year-old titular character, Tamon is the "wild boy" member of idol group F/ACE who portrays a confident and bold persona in public. On the inside, he has low self-esteem with his public image being a character forced upon him by his agency. Despite this, his feelings towards being an idol and his fans are genuine. Utage discovers his true personality after being sent to work for him, and decides to stick to his side to support him. She refers this side of Tamon as "Gloomyhara" (ジメ原, Jimehara) and his idol persona as "Hottiehara" (イケ原, Ikehara). Tamon grows to value Utage and starts to become conscious of Utage's life—sometimes becoming possessive of her in a side known as "Darkhara" (ヤミ原, Yamihara). One of the running gags is that when he becomes gloomy, mushrooms grow around him, literally turning his room muggy. Tamon has an older brother, Daiki, who inspired him to pursue an idol career.

Ouri Sakaguchi (坂口 桜利, Sakaguchi Ōri) Voiced by: Toshiki Masuda (voice drama), Shōya Chiba (anime) (Japanese); Brandon Acosta (English) Portrayed by: Haruki Mochida Ouri is the 17-year-old "prince" member who portrays a close relationship with Tamon. Born from family of entertainers, he has been active in the industry since a child and has many long-time fans. Popular for his refined and well-mannered demeanor, Ouri's true personality is that of a proud, arrogant, and violent man. He sees through Tamon's timidity and looks down on him, though both of them eventually become closer. Despite being initially hostile towards Utage, he eventually falls in love with her and has been trying to win her heart. Keito Tachibana (橘 敬人, Tachibana Keito) Voiced by: Tasuku Hatanaka (Japanese); Cody Savoie (English) Portrayed by: Kōhei Kamiyama The leader and later center of F/ACE, he is 21 years old. On the outside, he is a friendly and gentle young man who is excellent at cooking, with his own cooking show. However, Keito is ruthless and only sees his fans as a source of income. He wears glasses in private. Wanting to make money, he is strict against scandals and was initially unaware of Utage, but eventually comes to accept her as Tamon's emotional support. His intense obsession with money stems from his desire to send his five younger brothers to college and to make things easier for his parents. Natsuki Ishibashi (石橋 ナツキ, Ishibashi Natsuki) Voiced by: Kōhei Amasaki (Japanese); Kevin D. Thelwell (English) Portrayed by: Yūri Takahashi The "cute" member of F/ACE who is 20 years old. Fashionable and multi-talented, he produces his own cosmetics and composes his own music. His true personality is that of someone who likes cigarettes, alcohol, and pachinko. Being from Kansai region, he speaks in Kansai dialect in private. As a teenager, he indirectly caused injury to his then-girlfriend Asuka, which forced her to withdraw from an important martial arts match. Despite his growing success as an idol, he feels guilty and is unable to fully devote himself to his activities. Rintarō Kai (甲斐 倫太郎, Kai Rintarō) Voiced by: Ryūho Nagaoka (Japanese); Alex Hom (English) Portrayed by: Sora Yamato The 19-year-old rapper of F/ACE, Rintarō is the tallest and physically the strongest member of the group, and is active in sports and entertainment programs and as a model. He is quiet, cool, and mysterious, which is his charm. His true personality is that of a talkative otaku who can't help but talk nonstop about his favorite anime, "Sushi Musume" and his favorite character Kanpyo Roll. Rintarō became an idol because, like anime, he can evoke "emotions and stories that would not happen in normal life." Unlike the other members, he neither creates an idol persona nor talks much when he is nervous.

Wataru Fujita (藤田 渉, Fujita Wataru) Voiced by: Masaaki Mizunaka (Japanese); Aaron Campbell (English) The 32-year-old manager of F/ACE, Fujita is under a constant state of stress having to manage its members who all have personality quirks that are difficult to work with. He is aware that Utage's actions in support of Tamon go outside her job for doing household chores or even what a normal idol fan would be allowed, and approves of it. He acknowledges Utage has had a positive effect on Tamon, making him come out of his shell, which by proxy makes his own managerial job easier. Izumi Shiraishi (白石 泉, Shiraishi Izumi) Voiced by: Takako Honda (Japanese); Marwa Elda (English) The producer of F/ACE whom Tamon is scared of due to her strict personality. She does this to raise the group's popularity. Yuina (結菜) and Riko (莉子) Voiced by: Saya Fukuzumi (Yuina), Yurika Hirayama (Riko) (Japanese); Kayla Temshiv (Yuina), Taylor Murphy (Riko) (English) Utage's best friends at school and fellow fans of Tamon who are oblivious of Utage's connection with F/ACE. Homare Kinoshita (木下 ほまれ, Kinoshita Homare) Voiced by: Runa Sasaki (Japanese); Rebecca Chiara Marano (English) Homare is Utage's riajū younger sister who cannot understand her older sister's obsession over an idol. She would rather be idolized by other people instead. Nevertheless, Homare eventually becomes a fan of F/ACE herself and has Keito as her favorite member. Yamato Kinoshita (木下 やまと, Kinoshita Yamato) Voiced by: Ayaka Nanase (Japanese); Emily Neves (English) Yamato is Utage's younger brother and Homare's twin brother who cannot understand his older sister's obsession over an idol either. He prefers to focus on studies instead. Asuka Inoue (井上 飛鳥, Inoue Asuka) Voiced by: Misato Matsuoka The 22-year-old new teacher at Utage's school, Asuka is a fellow F/ACE fan whose favorite member is Natsuki. She and Natsuki are ex-lovers. Asuka continues to support him even after the two grew apart. Rinka Kai (甲斐 凜花, Kai Rinka) Rintarō's 17-year-old younger sister who is against her brother's profession. Rinka ran away from home and ended up befriending the wrong people. After Rintarō and Utage save her, she understands her brother's choice and becomes a fan of F/ACE, as well as a friend to Utage. Daiki Fukuhara (福原 大樹, Fukuhara Daiki) Tamon's 28-year-old brother whom occasionally gets mistaken for his younger brother. During college, he took Tamon to Tokyo and introduced him to dancing, which inspired him to become an idol. Despite having a talent in dancing himself, he chose to pursue a steady career instead. Daiki is married to his long-time girlfriend, Sayuri, and a father to one daughter, Momo.

Written and illustrated by Yuki Shiwasu, Tamon's B-Side was initially a one-shot published in Hakusensha's Hana to Yume magazine on August 5, 2021. It began its serialization in the same magazine on October 20 of the same year. As of June 2026, sixteen tankōbon volumes have been released. In February 2023, Viz Media announced that they licensed the series for English publication; the first volume was released on October 3 of the same year. A spin-off manga written and illustrated by Uzu Natsuno, titled Tamon's B-Side: F/ACE Off Stage! (多聞くん今どっち!? F/ACEオフステージ！, Tamon-kun Ima Dotchi!? F/ACE Ofu Sutēji!), began serialization in Hakusensha's The Hana to Yume Numa magazine on July 26, 2025. The spin-off is centered around the activities of the boy band F/ACE. The first tankōbon volume was released on March 19, 2026.

An anime television series adaptation was announced on June 12, 2024. It is produced by J.C.Staff and directed by Chika Nagaoka, with series composition and episode scripts written by Chiaki Nagai, characters designed by Yōko Itō, who also served as chief animation director, and music composed by Takashi Ōmama and Natsumi Tabuchi. The series aired from January 4 to March 29, 2026, on Tokyo MX and BS11. The opening theme song is "Sweet Magic", and the ending theme song is "Hana to Yume" (花と夢), both performed by the in-universe boy band F/ACE. Crunchyroll is streaming the series. Medialink licensed the series in South, Southeast Asia and Oceania (except Australia and New Zealand) for streaming on Ani-One Asia's YouTube channel.

A stage play adaptation was announced on March 5, 2026. It will be directed by Yū Fukuzawa based on a screenplay by Keita Kawajiri, with Yoshihiko Aramaki serving as the producer. The play is set to open at the Tennozu Galaxy Theater in Tokyo in September 2026.

A voice drama adaptation, featuring Takuya Eguchi, Toshiki Masuda, and =Love member Maika Sasaki, was included in an issue of Hana to Yume published on October 20, 2022.