Muromi-san

Takurou Mukoujima spends his free time fishing at the pier, where he unexpectedly catches Muromi, a mermaid unaware of her true nature. It takes meeting Takurou for Muromi to realize she's a mermaid, and her personality is characterized by naivety and a tendency to engage in reckless behavior, including overdrinking. This leads to frequent and unpredictable encounters for Takurou whenever he goes fishing.