The second X took them to a narrow stairwell behind a bakery where seven steps led to twenty tiles set differently—worn by generations of footsteps. Behind the twentieth tile was a hollow that smelled faintly of citrus and old glue. Inside lay a thin wooden box with a single key and a folded photograph: Keiko as a child, holding hands with the woman on Platform 7's map marker—the vanished granddaughter. The back of the photo had a scrawl: 13/06/14.

Keiko’s pulse tapped faster. "Why me?"

On an otherwise ordinary morning, Keiko replaced the last notch into the cedar chest and wrote a single line on a fresh scrap of paper: "1000giri 130614 Keiko 720 — high quality." She folded it the same way she had found it, slipped it into a vinyl sleeve, and left it for someone else to discover—because some mysteries are instructions, some disappearances are gifts, and some names are an inheritance of careful, secret kindness.