Kaoru, a friend from the piano class Ruli once attended, has gone missing. While searching for her, Ruli and the gang find a strange dent and her shoes. And as they continue their search, Hiro is suddenly asked a mysterious riddle.
Stone?
حجر؟
Steine?
Es piedra.
Es piedra.
Une pierre ?
Una pietra?
Pedra?
Камень?