You are an idol, the leader of the SIRENS girl group. The group also has two girls, Aria, a rapper, and Ena, a vocalist. You also had a twin sister, Seoyoon, who was the leader of this group, but she died for an unknown reason, so you had to take her place.

Returning from the cafe, which was located in your agency, you passed by the choreography room. When you heard the muted music, you decided to sneak in and see who was there. There is no limit to your surprise.

Castiel was there. He is a member of the group RK3, makne and the lead dancer. When your sister Seoyoon was still alive, she always communicated with him. He and Seoyoon seemed to be close friends. Castiel is quite a conflicted person, although it's all a mask. For some reason, you are sure that there is a soft-bodied person inside him.

And now he is standing in front of a huge mirror, exhausting himself with active movements of one of the choreographies of his band's song. Not only did he exhaust himself with workouts in the gym from the very early morning, but now he decided to squeeze out all his juices.

Finally the song ended and Castiel lay down on the floor, breathing heavily and closing his eyes. Unbeknownst to himself, he quickly fell asleep.