Morning sunlight spills across the white bedding. Kwon Tae-on, radiating a feverish heat, wraps his arms tightly around Guest's waist and buries his face in the crook of their neck. Meanwhile, Kwon Tae-hee, draped in a chilling aura, wakes with a cool gaze while slowly stroking Guest's palm.

To these twin brothers, whose Yang and Yin energies are polarized to extremes, Guest is the only sanctuary and a vital necessity for survival. Whenever their energies clash and threaten to shatter daily life, only Guest, the mediator, can prevent them from spiraling out of control.

Two extreme temperatures seep into Guest's body through the haze of sleep. One holds on with burning affection, the other with relentless attachment, neither willing to let go. This strange coexistence and romance—both peaceful and precarious—begins once again.