 Misuzu names a crow she finds —Japanese for "sky".Another major theme is the maternal bond, as the four heroines' stories, as well as Yukito's, revolve around their mothers, either biological or adoptive.Main scenario writer Jun Maeda commented that he prefers to include mothers in games if given the choice between only including a mother or a father, as is what happened with "Air", though he backs this up by noting that in bishōjo games, women are the main focus anyway.