Wikipedia
Konohanasakuya-hime or Konohananosakuya-hime (木花開耶姫, 木花咲耶姫 or 木花開耶姫; lit. "[cherry] tree blossom blooming princess" (her name also appears in a shorter form as "Sakuya-bime")), in Japanese mythology, is the blossom-princess and symbol of delicate earthly life. She is the daughter of the mountain god Ohoyamatsumi. She is often considered an avatar of Japanese life, especially since her symbol is the sakura (cherry blossom). Konohanasakuya-hime is also the goddess of Mount Fuji and all volcanoes.
Sakuya-bime is the wife of the god Ninigi. She met him on the seashore and they fell in love; Ninigi asked Oho-Yama, the father of Sakuya-bime for her hand in marriage. Oho-Yama proposed his older daughter, Iwa-Naga-hime, instead, but Ninigi had his heart set on Sakuya-bime. Oho-Yama reluctantly agreed and Ninigi and Ko-no-hana married. Because Ninigi refused Iwa-Naga, the rock-princess, human lives are said to be short and fleeting, like the sakura blossoms, instead of enduring and long lasting, like stones.
Sakuya-bime became pregnant in just one night, causing suspicion in Ninigi. He wondered if this was the child of another kami. Sakuya-bime was enraged at Ninigi's accusation and entered a doorless hut, which she then set fire to, declaring that the child would not be hurt if it were truly the offspring of Ninigi. Inside the hut, Ko-no-hana had three sons, Hoderi, Hosuseri and Hoori.
Shrines have been built on Mount Fuji for Sakuya-bime. It is believed that she will keep Mount Fuji from erupting,"In A.D. 806 a local official built a shrine near the foot of the volcano to keep it from erupting. The priests assigned the task of pacifying the mountain apparently neglected their duties because Fuji erupted with great violence in 864, causing much damage in a nearby province. The governor of that province blamed the priests for failing to perform the proper rites and constructed another shrine in his own territory, where he could make sure everything was done correctly. A fiery god of the mountain became at a later date the more peaceful Shinto goddess of Mount Fuji-- Konohana Sakuya Hime-- the Goddess of Flowering Trees."
"Konohana Sakuya Hime originally had little or no connection with Mount Fuji. Sometime between the 14th and 16th centuries, the belief arose among the people of the region that she would protect them from eruptions of the volcano as she had her newborn son from the flames of the burning bower." Konohana is now the principal goddess of Mount Fuji. Members of Fuji-ko have altars in their own home in which they worship Konohana Sakuya Hime. This group also lights a torch for Konohana Sakuya Hime at the fire ceremony at Fuji-Yoshida. but shrines to her at Kirishima have been repeatedly destroyed by volcanic eruptions. She is also known for having torn up the Yatsugatake Mountains, because it was higher than Fuji-san.