|Also Known As||Hainiryuun Ieasomuuru Jieda|
|Hair Color||Light Purple|
|Portrayed By||Yui Horie|
Hanyuu (羽入 Hanyū?, also known as Hanyuu Furude, originally Hainiryuun Ieasomuuru Jieda) is goddess who was sacrificed as part of the Watanagashi Festival centuries ago to atone for the sins of others. She serves as a sort of guardian angel to Rika Furude, one of the few people who can see her. She is the true deity behind the legend of Oyashiro.
Hanyuu was once known as the demon goddess of Onigafuchi under her true name, Hainiryuun Ieasomuuru Jieda. She traveled with her clan to the Onigafuchi swamp and tried to coexist with the human villagers there, but she was discriminated due to her horns. Riku Furude, the heir to the Furude Shrine, fell in love with the goddess and married her. They had a daughter named Ouka Furude, the first in a long line of humans to carry demon blood.
To protect the villagers from demons, Hanyuu had to sacrifice her husband and lost her ability to appear in front of humans. Nobody was able to see her other than her daughter. To combat a strange disease that was spreading throughout the country, Hanyuu created medicine and gave it to her daughter. However, powerful men desired the medicine for their political purposes, and her daughter was captured. Driven by fear for the safety of her daughter and bitterness from the betrayal of the very people she saved with her medicine, Hanyuu became corrupted as a demon and massacred the villagers. Her daughter, knowing she had become corrupted with evil thoughts, battled Hanyuu and successfully stabbed her with a sword. This brought Hanyuu back to her senses; however, knowing she would one day turn evil again, she begged Ouka to kill her using her own sword, the only weapon capable of killing a demon. Since Hanyuu's death, the villagers revered Ouka for driving away the "demon" and the legend of Oyashiro started.
Hanyuu appears as a young girl with light purple hair and two dark purple horns. Her left horn has a crack running down it. Hanyuu usually wears a traditional shrine maiden outfit.
Quiet, timid, and polite, Hanyuu is a sweet and innocent girl, despite her tendency to refer to herself with the pronoun "boku," which is generally reserved for boys. She is easily intimidated or frightened, and will whimper "Au au, auauau…" when upset or excited. When angry, however, her eyes turn red, and her voice becomes stern, serious and mature like that of a goddess or mature woman. Hanyuu's change in voice is similar to that of Rika Furude, whose cute childlike voice is likewise replaced by a mature women's voice.
Hanyū is extremely loving and carries a lot of guilt for the suffering experienced by Rika's friends. She often feels helpless or despairing due to her inability to influence the world around her to save her friends from their terrible fate in her spiritual form. All she feels she can do is apologize for her uselessness in protecting the ones she loves, which led to her habit of following those who are about to fall into paranoia or die and repeatedly apologizing, which only exacerbated their paranoia and hallucinations.
Contrary to the village's image of Oyashiro, Hanyuu is very timid, hates violence and suffering, and is devastated by the horrific acts that are committed in her name. Because of this, she expresses a strong dislike for Miyo Takano, who is only attracted to the legend of Oyashiro due to its bloody history. When the topic of Oyashiro arises, Hanyuu becomes especially irritated and discouraged when she hears her name used as a name of punishment and violence, declaring numerous times that she would never curse or punish anyone through torture nor "demoning away" (however, Rika does note that Hanyuu loves to stay in the Saiguden, which is full of torture tools, because according to Hanyuu it makes her feel "at home"). In scenes where Miyo Takano enters the Saiguden and revels in the violent history of Onigafuchi Swamp in front of the statue of Oyashiro, Hanyuu becomes very upset and repeatedly stomps on the floor in agitation. Since anyone at Level 3 or higher of Hinamizawa Syndrome can sense Hanyuu's presence, Jirou Tomitake (Level 3) and Shion Sonozaki (Level 4) were able to hear "a child jumping up and down on the ground" in Minagoroshi-hen, Watanagashi-hen, and Meakashi-hen.
- Though there is no confirmed relationship between the two, Hanyuu is strongly connected to Featherine Augustus Aurora from Umineko no Naku Koro ni.
- Featherine and Hanyuu share a similar appearance, specifically Featherine's dress and memory aid resembles Hanyuu's miko outfit and horns.
- When roughly translated, the kanji in Hanyuu's name (羽入) mean "feather" (羽 hane?) and "in" (入 iri?), which, when put together, essentially make "Featherine".
- The katakana that begin "Augustus" and "Aurora", "Au" (アウ), are the same as Hanyuu's catchphrase "Auau" (あぅあぅ). Bernkastel references this by referring to Featherine as "Auaurora".
- Lambdadelta mentions that Featherine's memory device was damaged, resulting in a change in appearance and personality. Similarly, one of Hanyuu's horns has a crack in it.