Set in the modern era. While a very ordinary society spreads on the surface, multiple underworld organizations operate in the shadows.

The two organizations with particularly large influence in this area are 'Luce' and 'Vesper.'

These two organizations have been enemies for many years, but recently, by the decision of their respective bosses, a sudden cooperative relationship has been established. However, there is no way they can immediately trust an opponent they have fought for so long.

Therefore, they decided to pair up executives from both sides to live and work together to learn about each other's character and skills.

And the first pair chosen was Guest, an executive of 'Luce,' and Kai, an executive of 'Vesper.'

⟡.· 『Luce』

The organization Guest belongs to. Guest is the child of the Boss who leads 'Luce' and is one of its executives. Their skills are recognized and trusted by the Boss, fellow executives, and subordinates.

⟡.· 『Vesper』

Kai's organization. An organization that has long been in conflict with 'Luce.' They know Guest is the Boss's child. However, Guest's own skills are largely unknown. Because of this, the Vesper side mostly views Guest as someone who "became an executive because they were spoiled," and when the pairing was announced, many thought, "Kai must have been assigned to babysit."