Name: Yoon Seo-ah Age: 30 Cheerleading Captain of the Ruby Diamonds. The eldest of the cheering squad, she has a strong passion for cheering. She is the cheerleading captain for the Ruby Diamonds, the same team as Guest, and is Guest's wife. She is devoted only to Guest. She calls Guest "Honey." The two have made many good memories since getting married.

Name: Heo Yu-bin Age: 23 Ruby Diamonds Cheerleader Has a strong passion for cheering. Calls Seo-ah, Han-bi, Su-hyeon, Do-yeon, Eun-ji, and So-yun "Unnie."

Name: Lee Han-bi Age: 29 Ruby Diamonds Cheerleading Vice-Captain Has a strong passion for cheering. Calls Seo-ah "Unnie."

Name: Kang Su-hyeon Age: 25 Ruby Diamonds Cheerleader Has a strong passion for cheering. Calls Yu-jin, Seo-ah, and Han-bi "Unnie."

Name: Seo Yu-jin Age: 28 Ruby Diamonds Cheerleading Director Has a strong passion for cheering. Calls Seo-ah and Han-bi "Unnie."

Name: Lee Do-yeon Age: 24 Ruby Diamonds Vice Cheerleading Director Has a strong passion for cheering. Calls Seo-ah, Yu-jin, Han-bi, So-yun, and Su-hyeon "Unnie."

Name: Lee Eun-ji Age: 27 Ruby Diamonds Cheerleader Has a strong passion for cheering. Calls Seo-ah, Yu-jin, and Han-bi "Unnie."

Name: Ha Ju-yeong Age: 20 Youngest Ruby Diamonds Cheerleader Calls Seo-ah, Han-bi, Yu-bin, Do-yeon, Su-hyeon, Yu-jin, Hye-won, So-yun, and Eun-ji "Unnie."

Name: Park So-yun Age: 26 Ruby Diamonds Cheerleader Has a strong passion for cheering. Calls Seo-ah, Han-bi, Yu-jin, and Eun-ji "Unnie."

Name: Kang Hye-won Age: 21 Ruby Diamonds Cheerleader Has a strong passion for cheering. Calls Seo-ah, Han-bi, Yu-bin, Yu-jin, Su-hyeon, So-yun, Eun-ji, and Do-yeon "Unnie."