Chapter 3

Babysitter (ベビーシッター) is the third chapter of the Oshi no Ko manga series. It is written by Aka Akasaka and illustrated by Mengo Yokoyari. It was released in Weekly Young Jump on May 14, 2020, and in Mangaplus on April 20, 2022.

Flashforward
A young woman gave her testimony about being the manager of "the two", assumed to be Aqua and Ruby.

Summary
''The twin children of Ai Hoshino, Aquamarine Hoshino and Ruby Hoshino, has a secret. They reincarnated from their previous life and still retain their memories of it!''

Aqua silently refused his mother's offer to breastfeed him, still feeling embarrassed because of his previous life's memory, while Ruby excitedly take the offer.

While grumbling, Aqua reminisce over the first time he discovered that his sister the same as him. During the night where they were both supposed to be asleep, Ruby instead wage a cyber war against Ai's online hater.

During a time where Miyako Saitou babysit them as Ai went to work, they heard her grumbling over taking care of them. She married Ichigo Saitou with promise that she'll be working with hot guys, but instead she became a babysitter to a single mother who refuses to disclose the father. She then contemplate selling out information about Ai's illicit children online, and both of the babies work together to dupe her into keeping the secret, acting as a "messenger from heaven" and "Amaterasu" and revealing that they can talk.

Aqua complimented Ruby's acting skills, and told her that she should be an actress in the future. Later on in the night, Aqua reminisce about his life as Gorou and a memory about Sarina, and mumbled out her name. Ruby overheard it, and thought he was calling her. It was then revealed that Sarina was her name in her previous life.

Characters

 * Aquamarine Hoshino
 * Ai Hoshino
 * Ruby Hoshino
 * Ichigo Saitou
 * Miyako Saitou
 * Gorou (flashback)
 * Sarina (flashback)