
S01E01 A Yakuza's Wife
Nagasumi, a teenage boy, is saved by the chivalrous mermaid Sun while drowning in the ocean off the coast of Seto Island. Mermaid society rules are strict — in order for both Nagasumi and Sun...
Nagasumi's mom and Sun go shopping for groceries, leaving Lunar alone with Nagasumi. Lunar plans to make her "slave" help her study for school since she is getting zeros on all her tests. Eventually it gets to the point where Lunar starts to come on to Nagasumi while outwardly stating that she would never fall in love with a human. Through many badly timed, but well-meaning errors, Nagasumi ends up being engaged to Lunar.
Nagasumi's in hot water after a beautiful, young mermaid named Sun saves him from drowning. The deep-sea sweetheart's dad is a merman yakuza prone to executing anyone who learns his family's scaly secret! Luckily, there's a catch - if Nagasumi agrees to marry Sun, he just might avoid sleeping with the fishes!