The neon glow of Tokyo’s Shinjuku station always made Kenji feel invisible—just another dark suit drifting through the damp late-night air. It was 11:14 PM. His shoulders were locked in their usual post-overtime tension, and his commute home felt, as always, like an exercise in sheer survival.

Then he saw it.

Resting on a bench near the quiet end of Platform 4 was a ordinary, plain black hardcover notebook. It had no title, no leather trim, no dramatic metallic clasps—just a basic, mass-manufactured journal someone must have dropped.