Sayaka Kotegawa

Sayaka Kotegawa is the owner and manager of the Palau branch of the "Dolphin" diving shop. She is the wife of Toshio Kotegawa, mother to Nanaka and Chisa, and aunt to the protagonist Iori Kitahara. Characterized by her elegant appearance and the sunglasses she always wears, she initially comes across as cold and difficult to approach. She shares a strained and seemingly distant relationship with her younger daughter, Chisa, but this cold dynamic is actually rooted in their shared social awkwardness and a major misunderstanding. Sayaka previously lost the hearing in her left ear due to a diving equalization error; to avoid discouraging Chisa's passion for diving, she kept the injury a secret, which unfortunately led to Chisa believing her mother was ignoring her when speaking from her left side. Despite her stern, aloof demeanor, Sayaka is a deeply caring mother who quietly watches over her family's safety and well-being.