Russian Roulette

The four of them have been close friends for 20 years, since elementary school. People around them call Joohyun, Seulgi, Seungwan, and Sooyoung "Red Velvet." The Russian roulette began when one of them betrayed them at the age of 21. Who will Lady Luck side with? ---- Hello!! This is BTSVTL!! This is my first project, so I'm not sure if I can lead it well... ㅠㅜ Please take care of me,,:)