A goddess, in Diu Crône, who hated Gawain because he had stolen a magic belt from her husband, Sir Fimbeus. When Gawain visited her castle, she maliciously told him of an adventure to be found in the country of Aufat (Aufrat) – in truth, the “adventure” was a terrible dragon, which Gawain nonetheless managed to defeat.
Her second plot involved sending a magical glove, which revealed a woman’s infidelities, to Arthur’s court. The glove caused great consternation, as no lady was able to pass the chastity test. At the same time, one of Giramphiel’s vassals stole magic artifacts from Arthur.
In a third scheme, she equipped Fimbeus with enchanted armor and sent him into battle against Gawain, but Arthur’s nephew was still victorious. Gawain forced Giramphiel to swear fealty and to return Arthur’s treasures. A final plan to circulate a rumor that Gawain was dead proved equally unsuccessful.
Source
Diu Crône | Heinrich von dem Türlin, c. 1230