The dolphin Chinatsu was born weak and was always bullied by the big dolphins. Only the girl Chinatsu accompanies it to swim and teaches it to catch fish. She is its favorite friend.
The girl Qianxia was born blind. She has no friends and lives in the darkness. However, she has the natural ability to get close to various sea creatures. They like her and can even understand her words.
In the late summer when the girl Chinatsu was 12 years old, the grown-up dolphin Chinatsu carried her into a deep cave. The dolphin Chinatsu disappeared, but the girl Chinatsu heard a boy's voice as gentle as the waves...
Is this boy full of sea breath Chinatsu the dolphin? Her fingertips stroked his handsome silhouette like ocean waves, his eyelashes as thin and soft as flowers in the sea, and his wet hair like water plants.
"I'll be your eyes," he said. "Next summer, I will come to you, I will carve words on the shells, and every season when the tide rises, I will send you a letter."
A few years later, the girl Qianxia came from a remote seaside village to a bustling city. When she finally opened her eyes, she found that she could not find her dolphin...
A strange city, a strange home. There are no waves, no sound of tides, no fish friends. There are only her brother who is cold to her, her sister who is always domineering, her classmates who use her as a shield, and the complex world of mortals that she cannot understand...
She is not afraid of anything. She is looking for the dolphin boy who once accompanied her in the blue sea and blue sky. It is the purest fairy tale in her heart...