Amanchu!

Futaba Ooki, who moved to a seaside town from a big city, spends much of her time documenting her life through photographs on her phone. She soon becomes fascinated with the ocean's vastness, but her contemplation doesn't go unnoticed, as local diver Hikari Kohinata happens upon her. Hikari, who nicknames Futaba "Teko," is drawn to her quiet nature and the two form a close friendship. Through Hikari's enthusiasm and their homeroom teacher Mato Katori's guidance, Futaba joins the school diving club and begins working towards her diving certification.