CORTIS short for “Color Outside the Lines” is a South Korean boy group under BIGHIT Music that debuted on August 18, 2025, with five members: Martin, James, Juhoon, Seonghyeon, and Keonho. The group is marketed as a “young creator crew,” with members actively participating in songwriting, choreography, and visual production, giving them notable creative involvement from the start of their career.

Their pre-debut single “GO!” introduced their experimental sound with trap beats and sharp synths. It generating mixed reactions from fans and critics but drew international attention. CORTIS made their debut with a self-titled EP and its title track, “What You Want,” which blended psychedelic rock guitar with boom-bap hip-hop rhythms, reflecting the group’s genre-bending style.

On March 6, 2026, CORTIS announced their second EP, GREENGREEN. “REDRED” was released as the EP’s lead single on April 20. The song became the group’s breakout hit, reaching number one on the Circle Digital Chart and Melon Weekly Chart. CORTIS became the first boy group to top the latter in 2026, while the song also set a new record for the most weeks at number one on Spotify’s Daily Top Songs South Korea chart by a K-pop group.

Since their debut, CORTIS has rapidly built momentum both domestically and internationally, developing a strong social-media following while gaining recognition for their hands-on creative approach and experimental sound.