A five-year-old boy develops a relationship with Ponyo, a young goldfish princess who longs to become a human after falling in love with him.
Ponyo has two forms: her fish form and her human form. As a fish, she is cute, but as a little girl, she is magical. She has thick amaranth red hair and has only two-piece clothing: an adorable little amaranth red dress with puffy sleeves and white bloomers. She behaves just like a regular five-year-old child, intelligent, adorable and mischievous, and, later in the movie, sleepy. She's very happy, sweet, and barefoot all the time. Brunhilde, or Ponyo as Sōsuke names her, is one of the main protagonists of the Studio Ghibli film Ponyo on the Cliff by the Sea and directed by Hayao Miyazaki. She is a magical fish descended from the Sea Goddess.
Sosuke is a 5-year-old boy who wears a sunshine yellow t-shirt and chocolate brown shorts. His hair is walnut brown with his hair shaven underneath. Also, he wears a sailor hat and binoculars. Sosuke is intelligent, smart, loyal, cute and heroic. He is willing to protect his friends (including Ponyo, starting from when she washes up on the shore near the house, stuck in a glass jar), even if doing so gets him in trouble with his mother or Ponyo's father (whom they hate). He is interested in the sea, especially since his father, Koichi, is the captain of a ship. He also knows that Koichi does his best for the family, as seen when Lisa gets angry at Koichi and chides him for abandoning her family on a cliff.