Yofune-Nushi

Yofune-nushi is a Japanese sea monster, living off-shore the Oki Islands.The story of the Yofune-nushi was recorded by Richard Gordon Smith in the book Ancient Tales and Folk-Lore of Japan, published in 1918. In the story, Yofune-nushi is a monster, living in the sea near the coast of one of the Oki Islands. It demands a tribute of a virgin girl once a year. A brave girl, called Tokoyo, dives into the sea instead of the girl intended as offering and defeats the unsuspecting monster. She also finds a cursed wooden idol that was causing a nobleman grief, thereby lifting the curse.
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[Japanese] A sea-serpent from Japanese mythology. It lived in cave under the rocks of the Oki Island's cost. Every year on the night of June 13, the serpent had to be offered a fair maiden. If this was refused, the creature would cause storms and destroy the fishing fleet. One year, a young girl, called Tokoyo, volunteered to go as the serpent's next victim. When the monster approached her, ready to devour her, she pulled a knife and slashed at its eyes, blinding it. When the serpent reared back in pain and confusion, Tokoyo slew it.