Onsen Musume are minor goddesses who live in every onsen. During the day Onsen Musume go to school in Odaiba, Tokyo to learn how to help more people learn about each Musume's respective onsen, and also to learn special arts that help guests relax and smile. One day they receive a proclamation from Sunahiko, the god who rules over all of the onsen, commanding them to become idols. The Onsen Musume form idol groups in order to compete in the newly-created idol tournament. The main character of the series is Yuina Kusatsu, the Onsen Musume for Kusatsu Onsen. With eight other Onsen Musume, she forms an idol group called "SPRiNGS". In school the nine members are known as the "weird ones", but as idols they aim to become the best Onsen Musume idol group in Japan.
A group made of 9 of the "weird students" at the Onsen Musume School. ; Yuina Kusatsu ; Saya Hakone ; Nanako Akiu ; Rinka Arima ; Izumi Dogo ; Ayase Noboribetsu ; Fuuka Arima ; Kanade Baden Yufuin
暁-AKATSUKI-
SPRiNGS's strongest rival. Other groups simply can't compare to their performances. Each member performs so well that they could easily become the centers of other groups. ; Hinata Kinugawa ; Kei Tamatsukuri ; Tamaki Beppu
LUSH STAR
LUSH STAR is the rival group that SPRiNGS gets along best with. Members of both groups were friends long before Sunahiko's proclamation. Their specialty is making everyone watching their performance feel more energetic. ; Uika Atami ; Erina Ibusuki ; Mana Wakura ; Koyuki Ginzan ; Honami Shirahama
Adhara
SPRiNGS's polar opposite, Adhara gives refined and exact performances. They charm audiences with their otherworldly aura. ; Kira Kurokawa ; Suika Hanamaki ; Nodoka Nyuto ; Tomoe Shirahone ; Momo Konpira ) ; Kurumi Tsukioka ; Seira Yunokawa
petit corolla
An idol group that studies SPRiNGS's performances. ; Hana Ikaho ; Rikka Ureshino ; Tsubaki Ito ; Arisa Kinosaki
Web Radio
Since April 24, 2017 Onsen Musume has been broadcasting a radio show every Monday titled "Onsen Musume: Present-ish web radio! Mimipoka!! YOU should come and play, yo!~". It is hosted by each of the characters. Once a month they broadcast the show live from Haneda Airport's International terminal's TIAT Sky Hall. On April 2, 2018 they began broadcasting a second Monday radio show, the "Onsen Musume Public Relations Department". Each episode is accompanied by a simple video. It is hosted by Seitaro Mukai, and Onsen Musume characters appear as regular guests.
Manga
; Onsen Musume 1-panel manga theater ; Onsen Musume 4-panel manga theater ; Web manga
Video game
"Onsen Musume Yunohana Collection" was released on August 3, 2018 for Android and iOS. It uses the player's location data to find onsen near them, and also includes original stories and over 100 characters.
