Thera was a Green-Jeweled Black Widow in The Invisible Ring. She was Lia´s best friend and her confidant during their journey to Dena Nehele and aslo later when Lia was Queen of Dena Nehele. She was Blaed´s wife.
During the journey Thera pretended to be broken but that didn't diminish her snappy temper. She helped to keep them safe by weaving illusion spells around the coach. She also helped Lia to make her Offering to the Darkness. When it was time to fight against the Hayllians, Thera weaved illusion spells around herself and Lia to swap places. During the battle Thera (pretending to be Lia) was seemingly injured to buy some time for Lia to release spells to destroy the enemy. Later was revealed that the internal organs that had splashed to the road were from a pig and that Thera was actually alright.
The last entry in Lia's journal (found by Cassidy centuries later) was written by Thera. It announced that Lia had died and that she was about to die in a few days in Grayhaven. The spot where she died was later covered by Witchblood.
Both Theran Grayhaven and Jared Blaed Grayhaven are descendants of Thera and Blaed from their mothers' sides. Theran's name is probably a tribute for Thera.