일급비밀 English TST Formerly Top Secret Is A Six-Member Previously Seven-Member Boy Group Under JSL Company. They Debuted In January 2017 With The Mini Album Time's Up. Members K Yohan And Ain Were Formerly Part Of The Boy Group NOM. Members K - Vocals Yohan - Vocals Ain - Leader Dance Wooyeong - Vocals Rap Junghoon - Rap Yonghyeon - Vocals Former Members Kyeongha - Rap