 First introduced in "Summer Knight", she reveals that she now 'owns' Harry's debt to the Winter Fae.When the Leanansidhe returned to the Winter Court with a powerful athame, Mab forced her to sell Harry's debt contract to her to keep the balance in the court.In "Dead Beat" Mab was shown to have the athame, which she now possesses because she locked the Leanansidhe away for a time until she could be shown to have thrown off the corruptive influence the tainted gift had had upon her.