The knight succumbs to lust and rapes a woman along the river, and it becomes a scandal around the kingdom.
A woman's true desire is...
Upon being brought to court and sentenced to death, the Queen gave him one last chance to redeem himself: to find the answer to the question of', "What do women desire most?"
...to have equal power over her husband!
He travels the lands asking every woman he can find the question, until he happens upon a party of twenty or so women. When approached, they disappear, leaving one old woman.
He asks the old woman the question, and she grants him the answer, but the knight is now indebted to her.
He then goes to the Queen's court with the hag, and answers that a woman's true desire is equal power over her husband or lover. He answers correctly, and then the hag asks that he repay her by becoming her husband, to which he reluctantly accepts.
He marries the hag, and on their first night, he is sullen and complains about his plight. The hag resolves that is better that he now has a loyal and loving wife and that it is his choice to stay with her. He leaves the choice to her (which was her desire) and she turns into a beautiful woman as a result. The End.