Twilight of the Gods
Loki's wife, illusionist and shapechanger
Sigyn is a relatively powerful warlock whose abilities include illusion and shapechanging. She is Loki’s current wife, and is apparently loose in the world. As of very recently, she is in Nithavellir.
For a long time, she held the cup that caught Nodhoggr’s venom before it could burn her husband, Loki. She has since left Helheim where he is imprisoned, bound with their childrens’ entrails, to return to Midgard.