Gideon is the animal to call of the Master of Beasts and part of his triumvirate along with Captain Thomas Carswell. However, their triumvirate doesn't appear to grant them similar benefits as Anita's triumvirates do. It's unclear whether this stems from Thomas having been just a regular human before being bound by Padma, or from their mutual lack of unity.
Gideon is six feet tall and square-shouldered, with hair that is somewhere between blond and brown. His eyes are yellow with orange pinwheels, weretiger eyes. He also has kitty-cat fangs both in his upper and lower jaws, because his master has forced Gideon to stay in tiger form for too long and he cannot come completely back anymore.
He first appears in Burnt Offerings, when he comes to St. Louis along with his master and the Vampire Council delegation. He along with Thomas are under the orders of Padma's son Fernando while Padma is dead to the world. Later that day Gideon and Thomas help their master recover from the injuries Anita has inflicted.
In Bullet, when their master is possessed by Marmee Noir, Gideon and Thomas are forced to help their master attack Anita. After Belle Morte uses the ardeur to overwhelm Padma and escapes, he forces Gideon and Thomas into helping him again, and although they could have stopped Belle, they let her run away.