Loathly lady
The loathly lady can be found in The Adventures of the Sons of Eochaid Mugmedon, in which Niall of the Nine Hostages proves himself the rightful High King of Ireland by embracing her, because she turns out to personify the sovereignty of the territory (and is therefore sometimes referred in scholarship as a 'sovereignty goddess').
The motif can also be found in stories of the earlier high kings Lugaid Loígde and Conn of the Hundred Battles.
In the Fenian Cycle of Irish mythology, Diarmuid Ua Duibhne was one of the most famous members of the Fianna.
One freezing winter's night, the Loathly Lady brazenly entered the Fianna lodge, where the warriors had just gone to bed after a hunting expedition.
The next day, the Loathly Lady rewarded Diarmuid's kindness by offering him his greatest wish—a house overlooking the sea.
On three separate occasions, Diarmuid's friends, envious of his good luck, visited the lady and asked for one of the new pups.
Each time, Diarmuid was angry and asked her how she could repay him so meanly when he overlooked her ugliness the first night they met.
On the third mention of that which he had promised never to speak of, the Loathly Lady and the house disappeared, and his beloved greyhound died.
Arriving in the Otherworld, he searched for the lady through green meadows filled with brightly coloured horses and silver trees.
When a stranger revealed that the King's gravely ill daughter had just returned after 7 years, Diarmuid realised it must be his lady.
In her capacity as a quest-bringer, the loathly lady can be found in the literature of the Holy Grail, including Chrétien de Troyes' Perceval, the Story of the Grail, Wolfram von Eschenbach's Parzival, and the Welsh Romance Peredur son of Efrawg associated with the Mabinogion.
The loathly lady also appears in the Old Norse Hrólfr Kraki's saga where Hróarr's brother Helgi was visited one Yule by an ugly being while he was in his hunting house.
The plot of the story begins when a Knight of King Arthur's court rapes a young woman when he is overpowered by his lust for her.
But as the Knight draws near, to his dismay, the group vanishes and turns into a loathly old woman (a hag), who offers to help him with his dilemma.
The Wife of Bath continues with her tale and says that the loathly woman asks the knight to marry her in return for helping him.
