Shark is a member of Seto Group initially summoned by Sun's father during the Michishio family's initial visit to the Seto family home to attack Nagasumi. In human form, he later becomes Nagasumi's P.E. teacher. By his thinking, the sooner Nagasumi dies, the sooner everyone can return home. He often acts on this logic, trying to eat him. According to him, the answer to all problems is by eating the person causing the chaos, be it Sun's or Lunar's fans or a suicide bomber from his own group. he often seen sleeping and he can transform in only a sharkhead, but also a whole shark as seen when he's in the sauna.

Michishio Nagasumi's life couldn't be any more normal. In an odd twist of events, during his summer vacation he ends up almost drowning in the sea. Luckily, the cute mermaid Seto San appears to save him. However, San is from a yakuza mermaid family and according to their law, if a human is to catch sight of a mermaid, either he or the mermaid must die. The only other way is for Nagasumi to be taken in as a family member, marrying San. In attempts to save both of their lives, Nagasumi asks for San's hand in marriage. Nagasumi's summer vacation reaped more then what he would expect, as he must now protect San from others finding her secret out. 

[Blog](http://koyap.jugem.jp/) | [Agency Profile](https://tsf-official.com/talent/takehito-koyasu/)

Koyasu is the most prolific voice actor in the industry, having been credited for over 700 roles as of April 2022.

Growing up, Koyasu skipped out on going to school to watch movies at home because he wanted to become an actor. It wasn’t until later that he became interested in voice acting after having seen [Galaxy Express 999](https://anilist.co/anime/1491/). After graduation he entered a voice acting school. In 1988, he made his voice acting debut, and got his first regular role a year later voicing [Gai](https://anilist.co/character/13374/) in [Tenkuu Senki Shurato](https://anilist.co/anime/2113/).

Though having voiced more characters in the medium than anyone else, he is probably most known for his role as [Dio Brando](https://anilist.co/character/4004/) in [JoJo’s Bizarre Adventure](https://anilist.co/anime/14719/). He has stated that he likes playing villainous characters.

Koyasu has taken over many of [Kaneto Shiozawa](https://anilist.co/staff/95424/)’s roles after Shiozawa’s passing.

Father of [Kouki Koyasu](https://anilist.co/staff/219102/).

__Non-Anime Roles:__

- Olivert Reise Arnor - The Legend of Heroes Series (VG)
- More - Metaphor: ReFantazio (VG)
- Mustang - Goddess of Victory: Nikke (VG)

The OVAs are new stand alone shorts with characters from the series and introduces two new ones. It is now the third year of school, San and Luna's dads are still being over protective. All the while Nagasumi has his hands full trying to keep everyone around him under control and rescuing damsels in distress. <br><br>
(Source: Anime News Network)

A young boy gets saved from drowning by a mermaid but, according to mermaid law, if a human sees a mermaid's true form, both have to be killed. The only solution to the problem is for him to marry her. But can they keep her secret from being found out? <br><bR>(Source: Animewaves)

Fujishiro Shark