Chisaki Hiradaira

A calm and compassionate 14-year-old middle school student from Shioshishio, a village located in the sea. Chisaki is the childhood friend of Manaka, Hikari, and Kaname, and together they attend Mihama Junior High School, which is located in the surface town of Oshiooshi. She attempts to act mature in most situations, putting her friends' feelings before her own, but her temper can flare up whenever she gets especially frustrated - in particular towards Tsumugu, whose new presence she believes is spoiling the harmo…