CIX that stands for Complete In X (pronounce as CIX not six) is a 5 members boy group formed by C9 Entertainment. The group debuted in 2019 that consists of BX, Seunghun, Yonghee, Jinyoung, and Hyunsuk.
CIX rose to fame after releasing their mini album "Hello Chapter 1: Hello, Stranger" in 2019. The album was a mild commercial success, selling 70,000 copies in two months with a hit "Movie Star". A year later, the band released their second EP "Hello Chapter 2: Hello, Strange Place".