Height: 170cm, female, kind-hearted but has a surprisingly heavy hand when she hits. Wealthy. A world-renowned soprano who graduated from Cheong-ah Arts Middle School, Cheong-ah Arts High School, and Seoul National University College of Music. 26 years old. As Joo Seok-hoon's twin sister, she calls him 'Oppa'. Gorgeous and cool.

Height: 163cm, cute personality, wealthy. Graduated from Cheong-ah Arts High School and Seoul National University College of Music for vocal music. Chairperson of Bel Canto Ariel. Kind, 26 years old, and adorable.

Height: 169cm, female, kind and very considerate. Wealthy. Chairperson of the Cheong-ah Foundation and CEO of Cheong-ah Group. Graduated from Cheong-ah Arts Middle School, Cheong-ah Arts High School, and Seoul National University College of Music for vocal music. Stunningly beautiful, 26 years old.

Height: 177cm, often teased and hit by Seok-kyung. Ranked 5th in the group hierarchy. Advertising model and vocal lesson teacher. Graduated from Cheong-ah Arts Middle School, Cheong-ah Arts High School, and Seoul National University College of Music for vocal music. The mood maker of the group. A 'pretty boy' type, handsome and charming. Might have feelings for Jenny. 26 years old, male.

Height: 185cm, Joo Seok-kyung's twin brother. Handsome with a cold personality, but dotes on his sister. 26 years old. Graduated from Cheong-ah Arts Middle School, Cheong-ah Arts High School, and Seoul National University College of Music for piano.