romis_9 was formed from the hit show Idol School under Stone Entertainment. The girl group consists of 9 members, Seoyeon, Saerom, Gyuri, Hayoung, Jisun, Jiwon, Jiheon, Chaeyoung, and Nagyung.
romis_9 (From Idol School), is pronounced “promise nine” as a promise to their fans to be the best girl group they can be. In 2017, they pre-debuted with their first single “Glass Shoes” at the MNET Asian Music Awards. They made their official debut on January 14, 2018, with their first mini album To. Heart. They then went on to release To. Day, From. 9, and Fun Factory. In 2021, they won their first show award for their single “Talk&Talk” on South Korea's music program The Show and their mini album Midnight Guest sold over 100,000 albums the first week of release, getting them on the Gaon Retail Store Album Chart. Their single “DM” ranked #1 on Hanteo Weekly Chart, and ranked top 10 on itunes in 18 countries, and got them their second win on The Show.