Mana Ashida
Director Sabu mentioned that the entire filming was done without a prepared script. He had reportedly done that because he wanted to have a natural reaction from the actors. The filming staff was told of this just before the production of the film began. Mana Ashida and Ruiki Sato, who played the roles of Rin's kindergarten classmates, therefore did not have a prepared script to follow during shooting. Instead, they spent one month with the film's assistant director going through each and every scene in detail before the actual filming.