DEAR. DOOR

Following the tragic loss of his girlfriend, police officer Kyung-Joon seeks nothing more than a quiet, solitary life. His only remaining comforts are tending to his houseplants and fulfilling his duty to apprehend criminals. However, his desire for peace is shattered when a routine police investigation into an enigmatic cult takes a terrifying supernatural turn, dragging him far beyond the boundaries of the natural world. Thrust unwillingly into a hidden realm teeming with demons, succubi, and monstrous entities, Kyung-Joon quickly discovers that the most dangerous threat among them is a powerful demon king known as Lord Cain. This formidable entity harbors a dark secret: his very survival depends on a specific source of mana that can only be drawn through a mystical "door" concealed deep within Kyung-Joon himself. Now bound to a nightmare he never asked for, the grieving officer faces an impossible dilemma. With a relentless demon king fixated on extracting the vital energy locked inside him, Kyung-Joon must navigate this perilous new reality. The haunting question remains—what exactly is Cain willing to do to force that door open?