- "I swear that by recording as much as possible in this book, I will do my utmost to fulfil all my promises. Someday. Somehow."
- —Keisuke Urashima
Born in 1917, Keisuke possessed a bad memory and used diaries and journals to help remember events and times.
Presumably the landlord of Hinata Inn, Keisuke fathered a daughter, Hina Urashima, born in 1934. During the beginning of the Second World War, Keisuke bought a French doll from the Imperial University of Tokyo in the hopes of returning it to working condition. Naming it Moe after the production tag on its neck, he kept the doll in one of the underground rooms of the Hinata Inn.
Keisuke’s promise to fix Moe wouldn’t be fulfilled until thirty-three years later, in 1999, when she is rediscovered by Keisuke’s great-grandchild, Keitaro Urashima.