The Lady of the Castle, Lady Bertilak, is one of the most important female characters in the poem Sir Gawain and the Green Knight. When in company, she always appears with an old woman by her side (who later turns out to be Gawain's aunt, Morgan le Fay). Two women appreciate women's vulnerability and strength in youth and age, and they are always together. The master of the estate (Bertilak) insists that Gawain mingle freely and sit between the two women at dinner, and Gawain finds them very hospitable.
However, Lady Bertilak comes alone to Gawain's chambers three mornings in a row, each time in a more alluring form: her last appearance was in a simple dress, and with a bare hair. Each time she comes to Gawain's bed at dawn when Gawain sleeps and plays tricky games of courtship and seduction with him. She is not what one would normally expect from a housewife. Her active sexual role is hardly more reflective of romantic heroines than actual medieval women." With one hundred and twenty-two lines of speech, she plays a key role in testing Sir Gawain's honor, loyalty, and most importantly, honesty through her sexual innuendo. Most interesting in these scenes is the dilemma Sir Gawain faces when he must be courteous to Lady Bertilak (Code of Chivalry) and at the same time loyal to his master. The twist comes when Sir Gawain realizes that Lady Bertilak was being used as a tool of seduction by her husband to test Sir Gawain. This betrayal leads Sir Gawain to "attacking all women for their deceit and betrayal". Her character plays an imperative role in the poem, as a full understanding of the scenes of seduction is essential to a full understanding of "the whole poem. It is also from Lady Bertilak that Gawain receives a belt that has the power to protect its wearer "from anyone who tries to hit him." However, by taking this belt, Gawain betrays his deal with the lady's husband, and Gawain vows to keep the belt forever to remind him of his sin of cowardice.