CHI CHI (치치) was a four-member girl group formed by Trophy Entertainment in 2011. Their name stands for ‘Creative Electronic House Idols’.
They debut as seven-member group, but after their second single Nara, Ji-U and Peace left the group. On October 23, 2013, CHI CHI’s choreographer, Reflexjun, posted a statement on Twitter regarding their current status, saying that CHI CHI had disbanded earlier that year.
Source: kpop wiki