Oshi no Ko Interlude Chapter 4 Recap: Aqua and Ruby’s Past

The Oshi no Ko manga written by Aka Akasaka went on hiatus on August 7, 2023, and during the hiatus a short-spin off titled Oshi no Ko Interlude began its run. This interlude is written and illustrated by manga artist by Mengo Yokoyari and began publication in Weekly Young Jump on August 10, 2023. Oshi no Ko Interlude has run for four chapters and highlighted different supporting characters in each chapter. Oshi no Ko will return from its hiatus on September 20, 2023.

Editor’s Note: There will be spoilers for Oshi no Ko Interlude chapter 4 below.

In Chapter 3 of Interlude, the story focused on Akane Kurokawa and Kana Arima’s rivalry. Chapter 4 of Interlude focuses on Aqua and Ruby Hoshino’s past lives and current life as brother and sister. Aqua and Ruby are the twin children of Ai Hoshino, the famed idol who was tragically murdered when the twins were just children. In Aqua’s past life, he worked as a doctor who assisted Ai during her pregnancy. Ruby formerly lived as a terminally ill child who had been Ai’s fan.

What Happened in Oshi no Ko ex Interlude Chapter 4?

Chapter 4 of Oshi no Ko Interlude opens on Aqua reading through a medical book as Ruby observes him from the kitchen. Ruby walks over to Aqua to read over his shoulder.  Aqua becomes distracted from his reading as Ruby’s long hair tickles the back of his neck. He tells Ruby that it seems silkier than it was before. Ruby becomes excited over Aqua noticing how straight and silky her hair is. Aqua tells Ruby “It’s a nuisance if you let your hair loose at home. Why don’t you tie it?” Aqua’s words upset Ruby, causing her to yell at Aqua that he should cut his bangs. Ruby angrily storms out of the room while Aqua expresses his confusion over her reaction. Ruby throws herself onto her bed with tears in her eyes. As she cries, Ruby mumbles to herself, “Sensei…You dummy.”

Ruby begins to reminisce about her past life when she was Sarina. While she was in the hospital, her and Gorou were discussing Ai’s various charms. Gorou expresses that Ai has 500 million things that make her charming to him, but Ai’s hair is a big part of her charm. Gorou admires how lovely Ai’s hair is and talks about it at length. It is only when Gorou looks at Sarina that he remembers she does not have any hair due to her medical treatments.

Sarina dreamed of growing her hair long like Ai, but her mother made her cut it. Her mother considered long hair as a burden if Sarina was hospitalized. Sarina’s hair was cut into a bob before she eventually lost her hair. Sarina sees how upset Gorou is over his comments about Ai’s hair and says she’ll try to grow her hair long one more time. If Sarina grows her hair out, she thinks she may look like Ai. Gorou feels uplifted by her comment and tells Sarina that it might be a bad idea. Teasing him, Sarina asks if it is because she would replace Ai as his favorite. Gorou tells Sarina it would be because he would have a new idol to admire.

In the present, Aqua remembers the very same conversation with Sarina when he was Gorou. This realization causes Aqua to panic in embarrassment. Sometime later in the week, Ruby comes home from a long day of work and has a bath. As she is getting ready to turn in for the evening, Aqua appears with a hair dryer. Aqua begins drying Ruby’s hair, telling her that long hair suits her and that he has a new favorite idol. Ruby smiles, happy that Aqua remembered their past promise.

The Oshi no Ko anime is available on streaming services such as HIDIVE. Yen Press is releasing the manga volumes in English.