This is a list of characters appearing in Higurashi no Naku Koro ni who, for one reason or another, have insufficient information to warrant an individual character page.
Aiko Maebara (前原 藍子, Maebara Aiko) is Keiichi Maebara's mother. She rarely makes direct appearances in Higurashi no Naku Koro ni. In the anime, her face is never fully shown. Aiko is very fond of detective novels, especially those of Agatha Christie. She once wrote a crime novel and has contributed to a crime novel contest. She graduated from a "humble women's university". Aiko inadvertently helps Keiichi murder Teppei Houjou by revealing the trick to the "perfect crime".
Yasunori Ryuuguu is a middle-aged man and Rena Ryuuguu's biological father. He was married to Reiko Ryuuguu after their meeting in Okinomiya, leading to the birth of Rena. However, Reiko's flourishing career caused a rift to grow between her and her husband. The family moved to Ibaraki for Reiko's job, forcing Yasunori to give up his own job and largely became a homemaker. After Reiko revealed her infidelity, Yasunori fell into depression. After the divorce, Yasunori received a large sum of money as part of the divorce settlement, though he rarely spent any of it. His newfound wealth made him a target for con artists, specifically Teppei Houjou and Rina Mamiya. In Tsumihoroboshi-hen, the two attempt to blackmail him via a badger game, though Rena kills Rina before the two can finish their plan. This also occurs in Tatariakashi-hen. In Minagoroshi-hen, Teppei and Rina again attempt to blackmail him, however Rena talks to her father about the family's affairs and inspires him to find a job, avoiding the situation altogether.
- Daisuke, the second son of the grocery store. He likes shooting, and wants to be a sniper someday.
- Keitaro, helped open Rika and Satoko's house in Watanagashi-hen.
- Makino, helped open Rika and Satoko's house in Watanagashi-hen.
- Takezou from the Makino tire shop. He likes Bonsai and Shakuhaci.
- The two men who assault Keiichi in Onikakushi-hen.
- Uncle Yoshirou (善郎おじさん) in Watanagashi-hen.
- Uncle Yoshiroh (義郎叔父さん) in Meakashi-hen.
Akihito Houtani (鳳谷アキヒト, Houtani Akihito) is the man Rena's mother, Reiko, left her husband for, first appearing in Tsumihoroboshi-hen. Initially he was a friend from Reiko's work, however their relationship quickly escalated. After he impregnated her, the two decided to marry and left both Rena and her father. Neither Rena nor her father have seen Akihito since. His surname is revealed in Higurashi no Naku Koro ni Mei, wherein it is revealed that he fathered Nao Houtani with Reiko before the two divorced.
Akutagawa (芥川) is a middle-aged man appearing exclusively in Yoigoshi-hen. He joins a suicide party traveling to Hinamizawa in June 2006. His reasons for committing suicide are unknown. On the drive towards the village, he details the events of the Great Hinamizawa Disaster to the rest of the party. He commits suicide via carbon monoxide poisoning.
Chiaki (千秋) is a woman appearing exclusively in Yoigoshi-hen. She joins a suicide party traveling to Hinamizawa in June 2006. Her reasons for committing suicide are unknown, though she hints that it is related to her husband's death. Her deceased husband left her with a large sum of money that she intends to bring with her to return to him in the afterlife. She commits suicide via carbon monoxide poisoning. However, Akira Otobe steals Chiaki's cash card after the party commits suicide. At the end of Yoigoshi-hen, he returns the cash card to her body.
Koizumi (小泉) is an aged military officer who befriended Hifumi Takano during World War II. Koizumi was an early supporter of Hifumi's research, however pressures from the government resulted in its ridicule and dismissal. In Matsuribayashi-hen, Koizumi's death before Showa 58 weakens the government's interest in Hinamizawa Syndrome. It is revealed that many in power do not favor of the research. In light of the UN Biological Weapons Convention, "Tokyo" concludes that secret research on bacteriological weapons would tarnish Japan's international image, and that decide that their funding could be invested more usefully. Miyo Takano desperately tries to convince them about the importance of the research and the revolutionary effect it would have on the scientific community, but she suffers humiliation similar to her grandfather when they declare her previously lauded theories to be too farfetched. They ultimately order her to finish her research, develop a proper cure for the illness within three years, and then disband the Irie Institution and destroy all evidence of the research. These events psychologically corner Takano and motivate her to become pivotal in "Tokyo's" political conspiracy, which ultimately results in the Great Hinamizawa Disaster.
Machi (マチ) is a young woman appearing exclusively in Yoigoshi-hen. She joins a suicide party traveling to Hinamizawa in June 2006. Her reasons for committing suicide are unknown. Machi is drawn to Hinamizawa due to rumors that she could see the spirits of her dead family members there. She commits suicide via carbon monoxide poisoning.
Reiko Ryuuguu, is a successful businesswoman and Rena Ryuuguu's biological mother. She was once married to Rena's father after their meeting in Okinomiya. However, a series of promotions led her to spend more time at work than with her family. After the family moved to Ibaraki, Rena's mother became romantically involved with Akihito Houtani. She repeatedly brought Rena with her to office parties and similar affairs in an attempt to become grow her relationship with Rena while diminishing Rena's relationship with her father. She eventually tells Rena that she plans to marry Akihito and asks Rena to come with her. Rena strongly disapproved, and her disapproval turned to rage when Rena's mother revealed she was pregnant with Akihito's child. After this, Rena's mother refused to meet Rena's father and communicated only through her lawyer. Rena and her mother only met one more time, during which Rena attempted to give her mother a letter written by Rena's father, however Rena's mother refused to read it. After this, Rena destroyed all of her mother's possessions in the Ryuuguu house and vowed to have nothing to do with her ever again. Rena's mother has not appeared since.
Ryuunosuke Arakawa (荒川 龍ノ介, Arakawa Ryūnosuke) is a freelance writer that works for an occult magazine. He appears exclusively in Yoigoshi-hen, where he joins a suicide party journeying to Hinamizawa in June 2006. Arakawa is very well informed on the occult theories surrounding the village about aliens and parasites, though not as well informed on the traditional legends of the demons.
Saburou Sonozaki is a member of the Sonozaki family working for the Prefectural Assembly.
Sawada is Mamoru Akasaka's younger colleague and a member of the Japan Self Defense Forces. He, along with Akasaka, investigate the ruins of Hinamizawa 20 years after the Great Hinamizawa Disaster in the aftermath of Tsumihoroboshi-hen. He is originally known as simply "Akasaka's friend", he was given the name Sawada in the Higurashi no Naku Koro ni Kai anime. He is voiced by Katsuhiro Ota.
Saki Ootori is a mysterious character attending St. Lucia Academy. She only appears once, in Utsutsukowashi-hen. Her appearance in the story implies she was going to have a major role later on, however the manga was abandoned after three chapters.
Yukie Akasaka is the wife of Mamoru Akasaka and mother of Miyuki Akasaka. In most fragments, she dies due to accidentally falling down a flight of stairs. She survives in Matsuribayashi-hen as Mamoru follows the advice of Rika Furude, who predicts Yukie's death and instructs him on how to save her from the accident.
Section manager Takasugi
Part of the Okinomiya prefectural police.
Part of the Okinomiya prefectural police. Waits in the command car during the raid on the Sonozaki residence.
Part of the Okinomiya prefectural police. Leads group A during the raid on the Sonozaki residence.
Part of the Okinomiya prefectural police. Leads group B during the raid on the Sonozaki residence.
Part of the Okinomiya prefectural police. Observes the timetables during the raid on the Sonozaki residence.
Hinamizawa Bus Stop
Tonegawa works for the River Bureau's Urban River office at the Ministry of Construction. Tonegawa is represented with altered sprites for Kuraudo Ooishi.
Arakawa works for the River Bureau's Urban River office at the Ministry of Construction. Arakawa is represented with altered sprites for Mamoru Akasaka.
Yoshimura is a freelance writer investigating the curse of Oyashiro.
Okano is represented with altered sprites for Tatsuyoshi Kasai.
Hoshino looks similar to Miyo Takano. In the visual novel, Hoshino is represented with altered sprites for Miyo Takano.
Nitta is represented with altered sprites for Kyousuke Irie.
Hotoda is represented with altered sprites for Rumiko Chie.
Oda is represented with altered sprites for Okonogi.