Susanoo, newly expelled from heaven, comes down by the river Hi in Izumo and finds an old couple weeping over a girl. They explain the arithmetic of their grief: they had eight daughters, the eight-forked serpent of Koshi has taken one a year, and this is the year for the last.
僕名謂足〈上〉名椎，妻名謂手〈上〉名椎，女名謂櫛名田比賣
“I am called by the name of Foot-Stroking-Elder, my wife is called by the name of Hand-Stroking-Elder, and my daughter is called by the name of Wondrous-Inada-Princess” — Kojiki, Sect. XVIII, tr. Basil Hall Chamberlain (1882)
The kanbun writes the three names outright — 足名椎, 手名椎, 櫛名田比賣 — with 〈上〉 marking the reading of a syllable, so what looks like an interpolation is the chronicle’s own gloss. Chamberlain’s calques take some unpicking: the parents are Ashinazuchi and Tenazuchi, and “Wondrous-Inada-Princess” is Kushinada-hime, whose name carries inada, the rice paddy — she is a field-goddess, and what the serpent eats every year is arguably the harvest. Susanoo asks for her, is given her, and then does the thing the story is remembered for: he turns her into a close-toothed comb and sticks her in his hair, which puts her both out of reach and directly under his protection while he works.
The work is a trick rather than a fight. He has the couple brew sake eight times refined, build a fence with eight gates, and set a vat at each; the serpent puts one head through each gate, drinks, and falls asleep, and Susanoo cuts it apart at leisure. In its tail his blade catches on something — the sword Kusanagi, which he sends up to Amaterasu and which becomes one of the three imperial regalia.
Then he restores Kushinada-hime and marries her, and builds a palace at Suga where he composes what the Kojiki presents as the first Japanese poem, about the eightfold clouds rising there. Their descendant, several generations down, is Ōkuninushi, who goes on to rule Izumo. She is enshrined with her husband at Yaegaki and elsewhere in Shimane, generally as a deity of good matches and of the rice crop — the second being closer to what her name says.