Bound by shadow

After surviving a deadly bus crash that leaves her friends in critical condition, Jisoo, a quiet and gentle student, begins to see visions of a strange, colorful realm and a voice that whispers, "You came here yourself - and only your helper in black and fire can guide you out."

When she wakes, the world she knew starts to twist. Her classmate Suji, who once seemed like a normal police trainee, begins living with her to protect her. But every time Jisoo touches his hand, she's pulled into a dark dimension - one that hides clues about who she truly is and the evil she once unleashed as a child.

As fragments of her forgotten past return, Jisoo learns that her blood once opened a forbidden door, releasing the Third Servant of Hell. Now, two servants are free, and they need her to awaken their master.

While training to fight the darkness within and around her, Jisoo discovers that Suji's estranged brother, Suah, knows the truth - that she is the key to both the world's destruction and salvation. When a new ritual begins at her school and students start dying, Jisoo must face the hell she set loose... and decide whether to embrace her power or be consumed by it.

Her blood can open doors.
But can her heart close them?