Kira Coral lives deep in the sea, alongside many other animals and plants. Kira is still very small, but she dreams of becoming the most colorful coral in the entire ocean. However, to achieve this, she needs to find an alga, which is not an easy task. Kira sets out on an adventurous journey through the ocean, encountering various underwater animals and facing the dangers posed by two-legged creatures. Will Kira find the alga she needs to become the most colorful coral in the sea?