He is a Kappa who has been living in the mortal realm for many years. He is in charge of gathering information regarding the location of the hunted demons. In the OVA, he has fooled persons into believing that his appearance is a disguise. He has a secret contact (whom he holds dear) that helps him get most of the clues of the cases. Both of them die at the hands of the demon that possesses Yukihime. In the manga, he tricks and betrays Enma and Yukihime.    (source: wikipedia)

It's Tokyo in the 1970s, and evil youkai (goblins) are attacking the human world. The "Youkai Patrol" - Enma, Princess Yukiko, Kapaeru, and Grandpa Shappo - are sent from hell to exterminate them.
 
(Source: Anime News Network)

[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)

Monsters are coming to the human world from the Hell in order to get human spirits. As people's minds are getting dirty, being attracted by the dirty spirits, the monsters break the rule to go to the human world. 
Tsutomu, a boy who goes to Yokai Elementary School, is suddenly assaulted by monsters. Those who save him from the monsters are Enma-kun, the son of Enma, Yukiko, a snow woman, and Kapaeru. They are members of Monster Patrol that are sent to the human world to arrest monsters. 
(Source: AnimeNfo)

[Wiki (jp)](https://ja.wikipedia.org/wiki/肝付兼太)

Enma is a character created by the genius manga artist Go Nagai. Now, the popular character makes his appearance in an alluring Japanese horror anime for adults. It's a hair-raising erotic suspense in which Enma takes on complicated and gruesome incidents caused by demons who lurk in the darkness. But humans have lit up the darkness of the night with neon lights and turned their world into one that never sleeps, so demons now lurk in the "darkness of the human heart." Unfulfilled hearts, suppressed hearts, despair,...such darkness of the heart is the place they lurk.
 
Enma is the Demon Prince of the Underworld, a demon "Born of Fire." His mission is to take back or destroy demons that have escaped to the human world from the Underworld. Along with his partner, Princess Yukihime, "Born of Ice," and the monster, Kapaeru, Enma sets up "Enma's Detective Agency." Tonight, like any other night, they will roam the sleepless city. Horrific incidents that could not possibly be human acts occur one after another. The stench of evil lingers at the scene... Enma's fire rips through the darkness!
 
(Source: Bandai Entertainment)

[Profile](http://www.enkikaku.jp/men'sprofile/sato_setuj-prof.html) | [Twitter](https://twitter.com/setsujisato)

Emma-kun, Yukiko Hime, and Kapaeru are members of a Demon Patrol that are sent to the human world to arrest demons.
 
(Source: Anime News Network)

Four grown demons (Enma, Yukihime, Kapaeru, and Grandpa Chapeauji) are part of a Yokai-Patrol searching for demons that have escaped from Hell into the human world. They form the group known as the Enma Detective Agency as a cover for their activities.
