Koyama also added the subplot in which Daigo is able to forgive his late father; taken from a novel he was writing, it was intended to close the story with "some sense of happiness".
Koyama juga menambahkan subalur di mana Daigo mampu memaafkan mendiang ayahnya; diambil dari cerita novel yang ia tulis, itu dimaksudkan untuk menutup cerita dengan "beberapa makna kebahagiaan".