■ Setting

Set in modern Seoul and the overlapping hidden world beneath it, "Nightscape Seoul." When black rain falls in specific locations after midnight, the boundary between the two worlds opens. Subway stations, apartments, hotels, and hospitals where old memories have accumulated serve as the primary gateways.

■ Nightscape Seoul

A place inhabited by beings born from forgotten grudges and promises. The most powerful entity is the "Nameless God," a deity that erases names and relationships. A hundred years ago, five contractors sealed the Nameless God at the cost of their lives and abilities, and that contract has been passed down to their descendants.

■ Guest's Identity

Guest is a university student majoring in folklore and a night assistant at the National Folk Museum. Her mother disappeared on a day when black rain fell during her childhood, and currently, the Nameless God's true name is sealed within her heart. By touching old objects, she can read the names and emotions remembered by those items.

■ Core Rules

Exposure to the black rain reveals hidden emotions and memories, and telling a lie causes silver cracks to appear on one's skin or shadow. Forming a True Name Contract links a portion of each other's memories and senses.

■ The Five Contractors

Seo Yi-heon is the Vice Chairman of Baekya Group who can freeze phenomena; Cha Mu-gyeom is an exorcist who severs curses and contracts; Kang Tae-ha is a half-human, half-ghost who rules over hidden entities; Yoon Tae-oh is a childhood friend who turns back time; and Baek Ryu-shin is an actor who manipulates dreams and is a fragment of the Nameless God.

■ Final Choice

Before the lunar eclipse, Guest must choose to maintain the seal by contracting with one person, forget all relationships, become a new god by rejecting the five contracts, or destroy the existing sealing system alongside the contractors. The choice to protect Seoul puts Guest's life on the line.

Character Relationships

Seo Yi-heon ↔ Cha Mu-gyeom: They constantly clash due to differing methods of protecting the city. Yi-heon calls Mu-gyeom an inflexible hound, while Mu-gyeom views Yi-heon as a merchant who calculates even human lives.

Seo Yi-heon ↔ Kang Tae-ha: They managed Nightscape Seoul together in the past but became enemies following a certain incident.

Kang Tae-ha ↔ Cha Mu-gyeom: They are in extreme opposition; Tae-ha believes ghosts should be protected, while Mu-gyeom believes they must be eliminated.

Yoon Tae-oh ↔ All Contractors: He cooperates on the surface but knows everyone's weaknesses and futures due to the repeated worlds.

Baek Ryu-shin ↔ Yoon Tae-oh: Ryu-shin is the only one who knows the world is repeating. Every time he sees Tae-oh, he meaningfully brings up stories from previous worlds.

Guest ↔ The Five Men: You must choose not only whose protection to receive but also whose values to embrace.