Fang's father Markus is Katagaria and his mother Bryani is Arcadian. Bryani sent her three Katagari pups (Anya, Fang, and Vane) to live with Markus and kept her three Arcadian children (Dare, Fury, and Star). When Vane turned Arcadian at puberty, he and Anya protected Vane from their cruel father and hid his secret from the pack. They grew up as a very tight-knit unit.
Anya was killed in a Daimon attack and Fang blamed himself for inadvertently alerting their enemies of the pack's presence. Markus also blamed Fang and Vane for drawing the Daimons, although he claimed it was due to the brothers' association with Dark-Hunters. They were sentenced to a timoria, which is being beaten and left for dead. Furthermore, Markus gave the same Daimons the location of where his sons had been left.
When the Daimons attacked Fang and Vane again, they stole pieces of his soul. He became stuck in the Nether Realms, neither dead nor alive. To the outside world, he appeared in a coma and Vane attributed his state to grief over Anya's death. Fang's mate Aimee Peltier was the only person who responded when Fang called out for help in their dreams. They had not bonded yet because she is a bear and interspecies mating is taboo. Nonetheless, she literally went through hell for him, tracking down the Daimons and killing them to release the pieces of Fang's soul.
She was nearly killed by demons at one point, but Fang made a deal with Thorn to help her in exchange for becoming a Hellchaser. Thorn gave him minimal instruction on hunting demons, which caused Fang to accidentally absorb a demon's powers and essence into his own body. The possession made him dangerous and unstable, which made it easy for the demon Misery to frame him for murder. Savitar knew Fang wasn't guilty, but he sentenced him to death as part of an elaborate ruse. Fang believed that Savitar would kill his entire family if he went on the lam, so he turned himself in. That selfless act ejected the demon from his body.
Fang is still a Hellchaser, but he and Aimee also became the owners of Sanctuary after her parents died.