The Oshi no Komanga series features an extensive cast of characters created by Aka Akasaka. The story follows a doctor and his recently deceased patient are reborn as twins to a famous Japanese musical idol and navigate the highs and lows of the Japanese entertainment industry as they grow up together through their lives.
Originally an obstetrician-gynecologist working at a hospital in Takachiho, Miyazaki Prefecture, in his mid-thirties named Gorou Amamiya (雨宮 吾郎, Amamiya Gorō), Aquamarine Hoshino (星野 愛久愛海, Hoshino Akuamarin) (also known as Aqua (アクア, Akua)) was a big fan of Ai Hoshino and also responsible for delivering Ai's babies. He met his demise after Ai's stalker killed him, causing him to be reincarnated as the son of Ai himself. When his mother was killed, he swears to discover the truth behind the murder. He theorizes that his father is in the entertainment industry and suspects he may be responsible for giving information about Hoshino's whereabouts, which leads him into pursuing a career in acting to find him and avenge his mother and murder his father. He temporarily starts dating Akane, but breaks up with her for her safety after she discovers his true motivation for tracking down his father. Although throughout the whole manga Aqua seems to come to understand the evils of his obsession with revenge against his father and learns to appreciate his new identity and life as Aqua, he ultimately still commits intentional suicide by inflicting further wounds on herself during a confrontation with Hikaru and pushing him into cliff into the sea, thereby committing murder-suicide to make it look like his father mortally wounded him, but Aqua supposedly managed to kill him via drowning in response. Shortly before his death, Aqua once again looks back on his life, believing that his actions made sense since all along he wanted to protect Ruby instead of seeking revenge and can safely leave first, giving Ruby hope for a better future. In the last moments of his life, he suffers from the cold and the inability to breathe, even expressing his desire to live again, but in the end Aqua dies peacefully, seeing the light and thinking that he hears a certain song.
Ruby Hoshino (星野 瑠美衣, Hoshino Rubii) was originally a terminally ill patient named Sarina Tendōji (天童寺 さりな, Tendōji Sarina) under the care of Gorou, she finds herself reincarnated along with her twin-brother, Aquamarine, as the daughter of Ai Hoshino. Before her reincarnation, Sarina obsessed over idols and dreamed to become one. A few years after being reincarnated, Ai is murdered. After Ai's death, Ruby trains to be an idol like her mother was. However, she is still not very good at singing. At the age of 14, Ruby auditioned to become an idol but was rejected through a fake phone call made by Aqua, who did not want her to follow in Ai's footsteps. Instead, Miyako offers Ruby the opportunity to form her own idol group under Strawberry Productions. The idol group, named B-Komachi in honor of Ai's old group, consists of her, Kana Arima and Mem-cho. As Sarina, she was deeply in love with Gorou, even though her feelings were one-sided as he never reciprocated at all, and these feelings resurfaced when she discovered that he reincarnated as Aqua, despite the fact he is currently her brother. At the end of the story, she gradually recovers from her brother's death and becomes a motivating idol for her fans. However, the last scene of the manga implies[a] that Ruby has essentially followed her mother's path, turning into an emotionally damaged and suffering person who hides it under the guise of lies about happiness and fun, thereby motivating and inspiring her fans.
A popular and charismatic pop idol. Ai Hoshino (星野 アイ, Hoshino Ai) lived in the countryside without her father, missing from birth, and her mother, who was arrested. She grew up in an orphanage, and at age 12, she was scouted by the president of Strawberry Productions, Ichigo Saitou, to become an idol. Ai did not believe she could become an idol due to not knowing love. Ichigo explains that she could lie and pretend to show love to her fans. She eventually became the face of the idol group B-Komachi. At age 16, Ai became pregnant with twins. She decided to give birth to them and hid these facts from the world so she could have the experience of a loving family, and took a hiatus from her idol activities. After the birth of her twins, whom she named Aquamarine and Ruby, she returned to work. At age 20, she was murdered by an obsessive fan who tracked her to her new apartment. In the last moments of her life, she realized that she really loved her children, and wished to be a bigger part of Aqua's and Ruby's lives, finally able to feel what it was like to truly love. Her death became the impetus for her son, Aqua, to pursue an acting career in order to seek revenge on her killer. Her name in Japanese can translate to "starry eye",[b] in reference to the six-pointed stars visible in both her and her children's eyes.
Kana Arima (有馬 かな, Arima Kana) was considered an acting prodigy as a child and known as "a genius child actor who can cry in ten seconds", and Ruby refers to her as "the child who licks baking soda". Kana first met Aqua when a movie she was featured in needed an extra and Aqua, who had accompanied Ai to the shoot, stepped in at the request of director Gotanda. As a teenager, the number of roles she got declined because she would always steal the spotlight from her peers. To survive in the industry, Kana decided to hold back her acting talent. Kana reunited with Aqua and Ruby in high school and found herself falling in love with Aqua, even though he does not reciprocate. She was still struggling to make it big as an actress when Aqua and Ruby persuaded her to join Ruby's idol group, B-Komachi, and Kana became the focal member of the group. After two years in B-Komachi, Kana leaves the group to focus on her revived acting career. She also has a deep, burning hatred for her rival Akane, which has stemmed from their childhood when Akane once idolized her. Towards the end of the manga, in one of Aqua's internal monologues, it is subtly implied that of all the girls around him, he really loved or at least sympathized with Kana as the girl closest to him in his life besides his sister. But he never manages to tell her about this before his death, while Kana herself is torn by the thought that she never managed to admit her love to him, although Aqua had already managed to understand this himself.
Akane Kurokawa (黒川 あかね, Kurokawa Akane) is a stage actress who signs up for a teenage reality dating show, My Love with a Star Begins Now (LoveNow), where she meets Aqua. During the show, Akane was an overlooked contestant who wanted to make her presence known in order to promote the Lalalie Theatrical Company she is affiliated with. On an episode of LoveNow, she accidentally scratched fellow cast member Yuki Sumi in the face. Viewer backlash resulted and Akane was targeted and sent insults and death threats on social media, which caused her to become suicidal. Aqua intervenes before her suicide attempt can succeed. Near the end of the show, her image improves due to the efforts of the rest of the cast, and Aqua kisses her during the last episode. They decide to stay together as a couple after the show ends to maintain appearances, and Akane later genuinely falls in love with Aqua, which only fuels Kana's jealousy and hatred for her. Akane once idolized Kana for her acting abilities as a child and strived to be just like her, but following a heated argument that led to Kana scolding and emotionally abusing her on their first meeting, the two girls grew to despise each other with a passion. Her approach to stage acting has her research the characters she is playing and infer much about their motivations and characteristics, much like method acting. Several months into their relationship, she figures out Aqua's plans to avenge his mother and vows to support him any way she can. However, Aqua breaks up with her soon after for her own safety. When Aqua enters the final phase of his plan for revenge against his father through Ai's biographical film, she vows to stop him from giving in to his darker impulses before he is irrevocably changed. To do so, she and her friends helps Aqua to prioritize on protecting Ruby, having caught up with the siblings' father's plan into manipulating his last assassin he manipulated into killing Ruby like his previous pawn did to Ai, with Akane disguise as "Ruby" while wearing an armor plate to ensure the real Ruby escapes to the concert, safely.
Ichigo Saitō (斎藤 壱護, Saitō Ichigo) is the president of Strawberry Productions. He is the husband of Miyako Saitō. Ichigo was responsible for the recruitment of Ai Hoshino to B-Komachi. He acts as the caretaker for Aqua and Ruby after Ai's death. Soon after Ai's death, he disappeared for a decade until Ruby tracked him down in order to get advice on her own plans for revenge on her mother's killer. Soon after, he was tracked down by Aqua as well, and expressing a fellow desire for revenge on the killer, assists Aqua with his plans.
Miyako Saitō (斎藤 ミヤコ, Saitō Miyako) is the wife of Ichigo Saitō and acts as the primary caretaker for Aqua and Ruby after Ai's death. She manages Strawberry Productions and keeps the business afloat after the disbandment of the original B-Komachi and the disappearance of Ichigo.
Mem-cho (MEMちょ) is a YouTuber and TikToker who signs up for LoveNow who is revealed to be aged 25 despite her appearance resembling a high school student. She pursued her dream of becoming an idol, but was unsuccessful due to her family situation during her high school days. She decided to become a streamer and lied about her age to gain many followers. After LoveNow, Aqua recruits her to B-Komachi. She was reluctant due to her age, but ultimately decides to join.
Pieyon (ぴえヨン) is an anonymous famous physical training Youtuber affiliated with Strawberry Productions, who coaches choreography for B-Komachi members. He makes over 100 million yen a year.
Frill Shiranui (不知火 フリル, Shiranui Furiru) is a student of Youtou High School's Performing Arts Program and one of Ruby's classmates. She is a multi-talented performer who can sing, dance, and act. She later is expected to play Airi Himekawa in Director Gotanda's and Aqua's planned Ai biographical movie after originally being chosen for the role of Ai before allowing Ruby to play the role following a self audition where she was impressed by Ruby's acting skill and conviction.
Melt Narushima (鳴嶋 メルト, Narushima Meruto) is an actor and model affiliated with Sonic Stage Productions. He was an arrogant and untrained actor when playing the male lead in the Sweet Today live-action adaptation, but still managed to deliver a solid performance for the final scene after being provoked by Aquamarine Hoshino. The experience humbled him and he has worked on improving his acting skills by the time he joined the stage production of Tokyo Blade. He later is expected to play Goro Amamiya on Director Gotanda's and Aqua's planned Ai biographical movie.
Minami Kotobuki (寿 みなみ, Kotobuki Minami) is a student in the Performing Arts Program of Youtou High School and a classmate of Ruby and Frill. In the show business industry, she works as a gravure model.
Yuki Sumi (鷲見 ゆき, Sumi Yuki) is a fashion model and a participant in the reality dating show The Beginning of My Love With An Idol or LoveNow. Initially imagining she would fade into the background, she used her character to create drama and interest.
Taiki Himekawa (姫川 大輝, Himekawa Taiki) is an award-winning stage actor affiliated with the Lalalie Theatrical Company, first seen as the main star of the Tokyo Blade stage production. It is later revealed that he is also Aqua and Ruby's older half-brother, conceived when his mother, an actress, Airi Himekawa cheated on his legal father with their biological father, Hikaru Kamiki; the latter was eleven years old at that time and an aspiring child actor joining the Lala Lai Theatrical Company when he was molested by Airi resulting in Taiki's birth. However, he himself remains unaware that he is the product of an affair.
Taishi Gotanda (五反田 泰志, Gotanda Taishi) is the film director who scouted Aqua and convinced him to become an actor when he saw his potential. After Ai's death, he recruited Aqua as his student at Aqua's request. He is one of the few people who knows the real identity of Aqua. He was once recruited by Ai to make a documentary film of her prior to her death. The creation of this biographical film of Ai's life is part of Aqua's plan of revenge against his father and Ai's killer.
Masaya Kaburagi (鏑木 勝也, Kaburagi Masaya) is a producer affiliated with an internet TV Station Dot TV!, and producer of the Sweet Today live-action adaptation and the webshow Dig Deep! One Chance. He seems to have deep ties with Ai at the past.
Yoriko Kichijouji
Voiced by: Shizuka Itō[9] (Japanese); Kelly Greenshield[8] (English)
Yoriko Kichijouji (吉祥寺 頼子, Kichijōji Yoriko) is the manga artist behind the popular manga series I'll Go With Sweet Today and Abiko's mentor. She also serves as producer for its live action drama where Kana is starring.
Abiko Samejima (鮫島 アビ子, Samejima Abiko) is the manga artist behind the popular manga series Tokyo Blade, and became a producer for its stage play after expressing displeasure with how its adaptation and script was progressing. She used to be Yoriko's assistant and student.
Hikaru Kamiki (神木 輝, Kamiki Hikaru) is one of the masterminds behind Ai and Gorou's murders, and the biological father of Aqua and Ruby. He was raped by a married adult actress who gave birth to his first child, Taiki, when Hikaru was only eleven years old. At age fifteen, he met Ai at the Lalalie Theatrical Company where he was teaching as an alumnus, and the two began a brief relationship resulting in her pregnancy with the twins. After Ai decides to abruptly end their relationship, this leads Hikaru to think that Ai used and abandoned him for her personal gains and would begin a vendetta against her, working with Ryosuke and Nino in order to tear her life apart. Though he initially sent Ryosuke to Ai which would lead to her murder, he originally intends to just scare her off as an intent to share his pain and suffering when she left him, hence not expecting Ryosuke's intentions. He is suspected by Aqua to have recruited an obsessive fan of Ai to commit her murder and has been involved in numerous orchestrated murders of other actresses. He is identified by Akane through clues gleaned from Aqua and her own research into Ai after she comes across him at a film awards ceremony, which leads Aqua to move forward with his plan for revenge. Once Hikaru found out from Aqua that Ai still loved him, as soon as he loved himself. At first, he appears to become regret his actions and to turn himself in to the police. In truth, it was all a lie, as he tricked Nino into attempting to kill his own daughter, Ruby. However, his plan failed when Aqua and his friends caught up with his lies, and manage to secure Ruby, with Aqua confronting his father after realizing he is beyond redemption, leading him to set a murder-suicide and toss both him and himself off a cliff, killing them both and thus stopping his murders.
Tsukuyomi (real name unknown) is mysterious girl in the woods who is a seemingly supernatural being aware of everything that transpires within the story, including Aqua and Ruby's reincarnation. She was originally a wounded crow who was rescued and cared for by Gorou and Sarina until it passed away. At Aqua's request, she manifests in the real world to portray the infant twins in 15 Years of Lies.
Ryosuke Kaihara
Ryosuke Kaihara is a mentally unstable university student shut-in who is an obsessive fan of Ai and Hikaru's contact. When he learned from Hikaru that Ai was pregnant, he was enraged by the revelation and with his help tracked her down, he was the one who murdered Gorou right after Ryosuke reveals to the latter that he was searching for Ai outside the hospital where she was staying by luring Gorou to a cliff near the hospital then pushing him to his death on the same day Ai gives birth to her twins, Ryosuke could not enter the hospital in fear of getting caught and fled. Four years later, he also learned about Ai's residential address from Hikaru, he arrived at her place on the day of her birthday which is also when she is planning to sing at a concert she is scheduled to appear pretending to give her a flower bouquet which has a knife concealed inside it as a fan and fatally stabbed her right in front of the twin's eyes; however Ai reveals to him that she has not forgotten every of her fan's names including him, especially the gift he gave her much to his horror, he immediately fled the apartment and committed suicide afterwards. It turns out his suicide was not by his volition, as Hikaru reveals to Aqua that he was the who murdered Ryosuke and fabricated it to look like he committed suicide out of pragmatic means to avoid evidences of his instigation for Ai's murder, not only that he was revealed to be Nino's boyfriend, and both are being manipulated by Hikaru for his murder spree. Although Nino survived and being arrested after Aqua and his friends caught up with Hikaru's last scheme on attempting to kill Ruby.
Notes
^Her eyes as an idol become similar to Ai's and she almost verbatim repeats her mother's words from the beginning of the manga that she and other idols are liars who lie about their happiness in order to inspire and motivate others in their difficult moments.
