The Yamainu (lit. Mountain Hounds or Wild Dogs) are a counter-intelligence squad led by Tetsuro Okonogi (although able to alternately be commanded by Miyo Takano) under the employ of Tokyo. While initially there to protect Rika Furude and the Irie Clinic, they are bribed by Takano to help destroy Hinamizawa. However, they betray her in the end when her schemes fail.

The men of the Yamainu look very similar to one another. They all wear the same uniform, gray cap and black shoes. Additionally, most, if not all of them, are always armed. Their way of travel is by a gray-white van or truck. The windows of their trucks are usually shadowed, so the victim can't identify them. A female Yamainu appeared as a nurse in Yakusamashi-hen. In manga, they tend to dress in casual clothes so they don't appear too suspicious to the public.

Besides appearing in the main series, they also appear in Hajisarashi-hen. They were asked by Takano to remove Keiichi's trunks, but Oishi called the police force. The Yamainu realized that they had no weapons since they were in a swimming pool, so they had no choice but to retreat. They are often seen using a white van for transportation. Okonogi also mentions the Yamainu in Ayakashisenshi-hen, referring to them as the Wild Dog Unit.



           When They Cry Villains

Higurashi: When They Cry
Gangsters | Juuza Amakusa | Rena Ryuuguu | Rina Mamiya | Shion Sonozaki | Shirou Hanada | Staff Leader | Tamae Hojo | Teppei Hojo |

Commanders: Miyo Takano | Nomura
Nail Ripper

Okonogi Tetsurou


Umineko: When the Seagulls Cry
Beatrice | Bernkastel | Eva-Beatrice | Featherine Augustus Aurora | Lady Lambdadelta | Virgilia | Yasu

Chiester Sisters Imperial Guard Corps
Chiester 00 | Chiester 45 | Chiester 410 | Chiester 556

Gaap | Ronove

Earls of Hell
Furfur | Zepar

Eiserne Jungfrau
Leader: Dlanor A. Knox
Cornelia | Gertrude

Seven Stakes of Purgatory
Asmodeus | Beelzebub | Belphegor | Leviathan | Lucifer | Mammon | Satan

Ushiromiya Family
Patriarch: Kinzo
Eva | Kyrie | Rosa | Rudolf

Black Battler | Erika Furudo | Kasumi Sumadera

Higanbana No Saku Yoru Ni (unofficial)
Nafumi Shintani | Yoshihito Kanamori

Higanbana Odoru