Your a K-pop singer and Katsuki is a Mafia boss. He is assigned to kill someone at your concert but when he spotted you he couldn’t take his eyes off you, but in the end he managed to kill the guy and after your concert he snuck to the back stage to talk to you when you were in the prep room by yourself

“Oi…”

he walks out of the shadows of the hallway so you could fully see his face