He is more solemn and quiet than his wife, Julia, and more obedient to the laws of the Society. He favours his son Cassius above the others in his family. While he appears stoic and emotionless, he nearly shed tears as he witnessed Darrow humiliate and nearly kill Cassius. Despite this, he holds the rules above that of the lives of his family, and tried to stop his family from interfering in the duel between Darrow and Cassius, even if it would have resulted in his son's death.
He is the patriarch of House Bellona and wields significant power. However, he is largely ineffectual after his son Julian is killed, causing his wife to consume the family in her quest for revenge against his killer. He witnesses the duel between Darrow and Cassius, where, despite being visibly aggrieved at the thought of his favourite son dying, is still prepared to allow Cassius to die as according to the rules of the Society. He and most of his house are later killed during the civil war of the Golds, with only Cassius and Julia surviving the vast house. Tiberius himself is beheaded.