(Kojiki) 木花之佐久夜毘売 木花開耶姫命 (Nihon Shoki)
"Princess Blossoming Brilliantly Like the Flowers of the Trees"
Fujisan Hongū Sengen Taisha 富士山本宮浅間大社
Shizuoka-ken, Fujinomiya-shi, Miya-chō 1-1
Sengen Jinja 浅間神社
Yamanashi-ken, Fuefuki-shi, Ichinomiya-chō, Ichinomiya 1684
Tsuma Jinja 都萬神社
Miyazaki-ken, Saito-shi, Tsuma 1
Kibana Jinja 木花神社
Miyazaki-ken, Miyazaki-shi, Kumano 9508
Konohanasakuya-hime is the main deity enshrined at the 1,300+ Sengen Jinja nationwide. Tne name Konohanasakuya-hime itself only came into widespread use during the Edo Period. Prior to that she was known as Asama-Ōkami (浅間大神, "Asama" is an alternative reading for "Sengen") or as Sengen-Daibosatsu (浅間大菩薩). Going back to the eight century she was referred to as Fukuji-kami (福慈神) in the Hitachi-kuni-fudoki
Section 27 - The Marriage of Ninigi and Konohanasakuya
One day Hiki-hono-ninigi encountered a beautiful young lady at Cape Kasasa. Immediately enamoured, he asked her whose daughter she was: the answer was Ōyamazumi-kami (22), and her own name was Konohanasakuya-hime (119B). He then asked her if she had any brothers or sisters and was told she had one sister, Iwanaga-hime (119B). He then told her he wanted to marry her, the response was that she would have to seek her father's permission. Ōyamazumi-kami was overjoyed at the proposal, and as well as presenting Hiki-hono-ninigi with a lavish dowry also gave him Iwanaga-hime as wife. On seeing the elder sister he was shocked at her ugliness and sent her back. He then spent one night of conjugal bliss with his chosen one.
Ōyamazumi-kami was shamed by Ninigi's actions and sent him a message explaining why he had given him both his daughters. If Ninigi had accepted Iwanaga-hime, the descendants of the Heavenly Deity (i.e. the Japanese emperors) "might live eternally immovable like unto the enduring rocks." (Chamberlain p140). If he had accepted Konohanasakuya-hime, the said descendants "might live flourishingly like unto the flowering of the blossoms of the trees." (Chamberlain p140). Because Ninigi had accepted only Konohanasakuya-hime, the life of his (and by extension Amaterasu's) descendants "shall continue only for the interval of the blossoming of the trees. For this reason, until this day the emperors have not been long-lived." (Philippi, p145).
Shortly after this, Konohanasakuya-hime informed Ninigi that she was carrying his child. He was surprised, saying that this could not have happened after having spent just the one night together and that the child's father must be an earthly deity. Her response was that if this were the case the child would not be born safely, but if the father was a heavenly deity the birth would be safe. She then shut herself in the parturition hut and at the moment of birth set fire to the hut. The baby born in the midst of the fire was Hoderi-no-mikoto (120A); he was followed by Hosuseri-no-mikoto (120B) and Hiko-hohodemi-mikoto (120C).