In a small fishing village, a gloomy middle school student named Kai meets a mermaid named Lu.
Shota Shimoda
as Kai Ashimoto (voice)
斉藤壮馬
as Kuniko (voice)
寿美菜子
as Yuuho Ebina (voice)
谷花音
as Lu (voice)
柄本明
as Ashimoto's Grandfather (voice)
伊藤静
as Isaki (voice)
鈴村健一
as Teruo Ashimoto (voice)
川島得愛
as Fuguda (voice)
チョー
as Ebina's Father (voice)
菅生隆之
as Ebina's Grandfather (voice)
篠原信一
as Lu's Father (voice)
佐々木睦
as Chief Priest (voice)
