ChaO

A future society where humans and mermaids coexist. One day, Stefan, an office worker who works at a shipbuilding company, is suddenly proposed to by ChaO, the princess of the mermaid kingdom! Without knowing why, Stefan ends up living with Chao!? Receiving Chao's pure and straightforward love, Stefan slowly finds himself drawn to her. What will become of their love!?

(Source: Official Website, Translated)