In the manga, she is kind, friendly, and is outgoing. Naru Osaka appears in Act 1 of the manga. She does not have as large a role in the manga as she does in the anime, and never develops relationships with either Nephrite or Umino. She is Usagi's best friend, and Usagi thinks very highly of her, telling her that she is a princess and that she is smart (she made an 85 on the quiz in Act 1). Her mother owns a jewelry store called OSA-P that is the scene of one of Jadeite's energy-stealing schemes in Act 1. Naru is very trendy and popular. She makes fewer and fewer appearances as the series progresses. Later, in Chibiusa's Picture Diary #4, Volume 17, we learn that Naru has a younger sister in elementary school named Naruru Osaka. Naruru is only Naru's sister in the manga.

Naru attended Juuban High School in the last arc, as she is shown in one panel to be eating lunch with Usagi.