Haru Soramachi is a seventeen year old girl who travels from Tokyo to the city of Onomichi to pursue her unusual dream of becoming a space fisherman. She was raised by her grandmother after her parents separated when she was young, and she shares a very fond and close bond with her. Her personality is characterized by a cheerful and energetic nature, which helps her easily make friends with those around her. She also has a soft spot for cute things, particularly cats.

In the story, Haru arrives in Onomichi as a newcomer, having applied to join a new generation of fishers who work in outer space, a profession created after the Earth's oceans were depleted of fish. Due to a misunderstanding with two other candidates who have already begun their training, she is launched into space for her first fishing mission without even being fully aware of the situation. Throughout the narrative, she is portrayed as a novice compared to more experienced senior fishermen, learning the ropes of this unique vocation. Her primary motivation is to achieve her goal of becoming a successful space fisherwoman, chasing the dream that brought her to Onomichi. As a space fisherman, her notable abilities are related to piloting a vessel or mecha to catch fish in the extraterrestrial environment, with her early attempts bearing the mark of a beginner learning a complex new skill.