Sif

The whole story goes like this:

---

Loki's son was tied up with a chain because he was a wolf, so Loki was mad at the rest of the Æsir. He was maddest at Thor, so he snuck in at night and shaved Sif's head because Sif was Thor's wife. Thor immediately knew that it was Loki who did it, so he sent him to the Dwarves who could Sif new hair. A dwarf called Dvalin made new hair for Sif as well as the magic spear Gungnir as a gift for Odin and the magic ship Skidbladnir as a gift for Frey. Loki was happy so he yelled that Dvalin was the greatest of all smiths, but another dwarf named Brok heard and made a bet with Loki that a third dwarf, Sindri, could make better gifts for the Æsir. If Loki won, he would cut off Brok's head, and vice versa. So Sindri made 3 gifts: a golden boar called Gullinbusti, a golden ring called Draupnir, and a magic hammer called Miolnir. They brought the gifts to the Æsir and Sif got her hair back, but Loki ended up losing his wager. However, Brok decided to be nice and not cut off Loki's head, so he sewed his lips together instead. Later Loki tore out the stitches, which is why his lips were scarred and uneven.

Sif was the wife of Thor. She was known for her golden hair (which was shaved off one night by Loki, but that's another story).