Natsuki stood at the threshold of his own apartment, the USB drive in one hand, his camera in the other. He could hear Marin’s soft breathing from the couch. He could hear, through the wall, the low thrum of Renji’s music.

That night, he confronted her. Not with anger, but with a photograph. A beautiful, grainy shot of the two of them through the rain-streaked window of a ramen shop. Marin’s face went white, then red. “You’re following me?” she whispered. “You’re spying on me?”

Three months later, Natsuki’s photo—titled “The Cuckold’s Light”—won an underground art prize. Renji had moved on to a new target. Marin had moved out. Alone in the darkroom, Natsuki developed a new roll of film. It was all empty rooms. Doorways without people. Shadows where lovers used to stand.

Natsuki raised his camera. The auto-focus whirred. Through the lens, Marin and Renji looked like a painting—two figures in a gallery of betrayal. He pressed the shutter. Click.

One night, Natsuki came home to find Marin asleep on the couch, still in her work clothes. On the coffee table lay a USB drive. Inside: a video file. He clicked play. It was Marin and Renji in a love hotel. But the camera angle—it was from a hidden camera Renji had placed in their own bedroom weeks ago. Renji wasn’t just sleeping with Marin. He was filming Natsuki’s life.