Encounter with the Black Cat in the Deep Sea

In the depths of the ocean, a girl with blue hair encounters a mysterious black cat. Dressed in a sailor outfit, she reaches out to the cat amidst sunken ruins. The cat swims as if guiding her, inviting her into an unknown adventure. In the bubbling water, they share a quiet secret. What legend of the sea lies hidden, stirring the girl's heart? What story awaits?