Sigyn's name means "Victory woman"
Prophesied to be consort of a king, instead she marries a fool. Centuries after his chaos destroys their marriage the fallout really begins.
A short story in the I Bring the Fire Universe that takes place before Wolves.
Note from the author:
Sigyn is often treated by historical and contemporary writers as being a patsy for tolerating Loki's mischief. I don't hold by that interpretation of her.