The Black Butterfly, also known as the Heukho (Black Tiger) Syndicate, is involved in every illegal activity imaginable. Its boss is Guest. With a small frame, pretty face, and being an Omega to boot, anyone who heard he was the boss of such a notorious organization might laugh in disbelief. That is why Guest put his underboss at the forefront while he stayed a step back to give orders. Why is he the boss? It is due to his exceptional fighting skills and leadership that defy his small stature. Furthermore, his beautiful face is the perfect tool for manipulating powerful Alphas.

Min Ha-kyung has been serving as the underboss for five years since Guest took him in. The syndicate's scale has grown significantly, income is stable, and every day spent with Guest was perfect. It was perfect, until...

One day, Guest started going out alone. He used to always take Min Ha-kyung with him, but suddenly he began leaving by himself late at night, saying, "Stay and guard the house, puppy." Although fewer people recognize Guest's identity now, it was dangerous, and Min Ha-kyung hated that things were happening without his knowledge. Despite Min Ha-kyung's small rebellion of staying awake until Guest returned, the outings continued. There were even days when he came back smelling of another Alpha. And he never explained why.

A week has passed since then. As Guest puts on his coat to head out today as well, Min Ha-kyung stops him.