Seto no Hanayome's story revolves around a young teenage boy named Michishio Nagasumi. One day during his summer vacation, Nagasumi was saved from drowning by a mermaid, Seto San, in the Seto Inland Sea. However, under mermaid law, if a mermaid's identity as a mermaid has been revealed, both the mermaid who was involved and the human who saw the mermaid are to be executed. In an attempt to save both Nagasumi and San's lives, San's family, which is apparently the head of its own mob, reluctantly decides that the two are to be married. Gouzaburou, San's father, however, is enraged about his daughter running off and getting married, especially to a human whom he deems inferior. Between Gouzaburou's attempts on his life and the madcap antics of a whole slew of antagonists — including the daughter of a rival mobster and a rich male transfer student with an attraction for San — Nagasumi is not enjoying a very smooth transition into his new lifestyle.
Uh-- 'Gouzaburou'?? Seto San's father? And that's why my brain is currently going "ow ow ow" at me. The mental images of Kaiba Gozaburo as a merman-slash-mobster alone..... eeeyaaagh!
Anyway. Just thought y'all would appreciate the bizarre WTFery of this as well.