Yomi
Yomi or Yomi-no-kuni (黄泉 or 黄泉の国 "Yellow springs/wells"?) is the Japanese word for the land of the dead (World of Darkness). According to Shinto mythology as related in Kojiki, this is where the dead go after life. Once one has eaten at the hearth of Yomi it is impossible to return to the land of the living. Yomi is comparable to Hades or Sheol and is most commonly known for Izanami's retreat to that place after her death. Izanagi followed her there and upon his return he washed himself, creating Amaterasu, Susanoo, and Tsukuyomi-no-Mikoto in the process (See Japanese mythology).
This realm of the dead seems to have geographical continuity with this world and certainly cannot be thought of as a paradise to which one would aspire, nor can it appropriately be described as a hell in which one suffers retribution for past deeds; rather, all deceased carry on a gloomy and shadowy existence in perpetuity regardless of their behavior in life. Many scholars believe that the image of Yomi was derived from ancient Japanese tombs in which corpses were left for some time to decompose.
The kanji that are sometimes used to transcribe Yomi actually refer to the mythological Chinese realm of the dead called Diyu or Huángquán (黄泉, lit. "Yellow Springs"), which appears in Chinese texts as early as the eighth century BCE. This dark and vaguely defined realm was believed to be located beneath the earth, but it was not until the Han Dynasty that the Chinese had a clearly articulated conception of an underworld below in contrast with a heavenly realm above. With regard to Japanese mythology, Yomi is generally taken by commentators to lie beneath the earth and is part of a triad of locations discussed in Kojiki: Takamahara (高天原 alternatively transliterated Takama-ga-hara?, lit., "high heavenly plain", located in the sky), Ashihara-no-Nakatsukuni (葦原の中つ国 lit. "central land of reed plains", located on earth?), and Yomo-tsu-kuni (黄泉国?) or Yomi-no-Kuni (黄泉の国 lit. "Land of Yomi"?, located underground). Yomi has also often been associated with the mythological realm of Ne-no-Kuni (根の国 lit. "Root Land / Land of Origin"?), also known as Ne-no-Katasukuni (根の堅洲国 lit. "firm/hard-packed shoal land of origin"?); perhaps the latter was meant to be underwater?
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