"Kaba no Potomas" centers around Potomas, a cheerful and mischievous baby hippopotamus who lives in a whimsical world filled with anthropomorphic animals. The narrative unfolds in a series of episodic adventures, each highlighting Potomas' playful antics and interactions with his friends and family. The setting is a vibrant, colorful environment that blends elements of nature with imaginative, childlike fantasy.

Potomas is characterized by his boundless curiosity and love for exploration, often leading to humorous and lighthearted situations. His best friend, a young rabbit named Usako, frequently joins him on his adventures, providing a contrasting personality with her cautious and thoughtful demeanor. Together, they navigate everyday challenges, such as solving small problems, learning new skills, and understanding the world around them. The series emphasizes themes of friendship, cooperation, and the joy of discovery.

The supporting cast includes Potomas' family, particularly his mother, who serves as a nurturing and guiding figure, and his younger sibling, who often mirrors Potomas' playful nature. Other recurring characters include a wise old turtle, a mischievous monkey, and a shy bird, each contributing to the dynamic and diverse community that Potomas inhabits. The interactions between these characters are central to the narrative, showcasing their unique personalities and the lessons they learn from one another.

The plot is driven by simple, self-contained episodes that focus on relatable childhood experiences, such as playing games, overcoming fears, and celebrating small victories. The tone remains consistently light and optimistic, with an emphasis on humor and gentle life lessons. The series avoids complex conflicts or dramatic tension, instead prioritizing a sense of wonder and innocence that resonates with its target audience of young children. Through its charming characters and episodic structure, "Kaba no Potomas" offers a delightful and engaging portrayal of early childhood adventures.