He is known as "Master" to Eon at the start of the first book, but when Eon becomes a lord, Brannon becomes known as Heuris Brannon, and briefly as Lord Brannon.
Heuris Brannon raised 6 potential candidates before Eon, and was told that if he did not secure the apprentice then Brannon would be ruined as he had no more money to raise another candidate.
He allows Chart, the disfigured boy of his unmarried body servant, to stay in his kitchen, which shows he is kinder than other masters. He also shows concern for Eon by asking him if his injury pains him much. He does not let Eon into the moon garden in fear of his Eona coming to the surface and ruining their scheme.
Before the twelfth day celebration, Eon and Brannon are offered some lime juice by a servant, who says that it is from Lord Tyron. During the ceremony, Brannon falls extremely ill and dies. Since Brannon had no family to prepare his tomb, Eon becomes his offical mourner. Eon suspects that Brannon was killed by Lord Ido, the Rat Dragoneye. However, when Kygo asks Eon to be his second mourner for his father, it is revealed that Brannon, as well as the Emperor, might have been poisoned by the royal physicist. Eon later confronts Ido about this, telling him that she knows he killed him. Lord Ido does not explicitly say whether or not he killed Brannon, but it is generally assumed that he is the killer.
Eon and Brannon had mostly a master/servant relationship, although Eon mentioned that 'he had been as much the creator of Lord Eon' as she was, also giving the impression that she missed Brannon. She also said she wanted to tell his master about many things including the folio and her dragon's name. However, when Brannon dies and Eon inherits his estate, she looks in his room and finds that Brannon had kept her needle tube, which she had left behind, in a precious, expensive box in his drawer. From this she draws the conclusion that he had loved her. Eon said that she had always known this, but pushed it down deep inside of her and denied it. After all, there wasn't much she could do about it. There had been several hints about Brannon's affection towards Eon; many times he shows his fondness physically, and other times through his dialogue it is apparent. Near the beginning of the book, Eon realizes that if she failed, Brannon would not need her anymore. It is then that she has the idea that she could 'offer him a girl's body' since she has seen it in his eyes.
After his death, it is revealed that Brannon crippled Eon to hide Eona and to gain power and money by smashing her hip with a hammer. He secretly confided to Chart that he was sorry and he thought he had nearly killed Eona.
Even though he is around 40 years old, he is described as elderly looking, probably due to the fact that his dragon took some of his Hua when he was the Tiger Dragoneye, making him look older than he is. He is described as having a shaved head.