Main characters: Kang Haechan -17 years old -the only son in his family -bestfriend with Taeyong, Yuta and Ten   Kim Hyoyeon -27 years old -has no family -bestfriend with Jessica and Seohyun   Nakamoto Yuta -17 years old -japanese -has one step-brother named Byun Baekhyun   Byun Baekhyun -25 years old -work as a private investigator -hates Yut