Who is Lunete from Arthurian Romances and what is their importance?

Lunete is maidservant to Laudine. She rescues Yvain when he battles the knight by the brook by giving him a magical ring. She then convinces Laudine that Yvain is far worthier than her former husband, which results in Laudine's marriage to Yvain. When Yvain doesn't return to his wife in a year, as promised, Lunete is charged with treason. Yvain ultimately saves her, and she facilitates the reconciliation between Yvain and Laudine.