Marin Chan is one of the main characters in the anime series 'Umi Monogatari.' She is a cheerful and optimistic sea dweller who embarks on a journey to the world above the sea. Her kindhearted nature and determination drive her to help others, often with her sister Urin. Marin's role in the series involves discovering the intricacies of human emotions and forming a unique bond with Kanon, a human girl. Together, they face challenges that test their friendship and the power of light against darkness.