- "We do not offer second chances."
Caius is a vampire, one of the three ancient leaders of the Volturi, who are based in Volterra, Italy, and who, according to Edward Cullen, lead a very civilized lifestyle. Caius is married to Athenodora, who lives a very retired life. He is the most ruthless of the three leaders, even more ruthless than Jane and Aro put together.
Caius was born around 1300 B.C., and at some point became a vampire. He was born at least a century before Aro and transformed into a vampire in his late 40s.
Caius met Athenodora after running afoul of the Romanian coven, and they began traveling together as a bonded pair, with her later becoming his wife. When they came across Aro, he was quite taken of the vampire's ambitious but long-ranged plans of domination. By the time they met, Aro had already formed a coven with a talented named Marcus. Caius was immediately attracted to the idea of joining forces with the gifted vampires. Though Caius had no psychic gift, Aro was drawn to his ambition and passionate capacity to hate; which was a great potential for manipulation in what could be both a weakness and a strength.
Aro's sister Didyme joined them quickly afterwards, and later Aro's wife, Sulpicia. Aro and Caius were in agreement after Didyme's death had devastated Marcus that the wives must be protected at all costs. By bringing more vampires into the Volturi coven, they brought about his ultimate goal: a war against the Romanians. After the Romanians almost destruction, Caius became satisfied to spend his time punishing offenders of Aro's law due to Chelsea's power that kept him bound to the coven.
Some 2000 years before Breaking Dawn, he was nearly killed in a fight with a werewolf, which prompted him to hunt them to near extinction. He also took part in the extermination of the immortal children and the cleaning up after the Southern vampire wars, making sure that newborn armies and their creators were destroyed.
In New Moon, after Caius, Marcus, and Aro turn down Edward when he asks them to kill him, Aro offers him a spot with the guard, which suprises Caius, but he turns it down. But, the three send Demetri and Felix after him when they smell Bella and her blood. After waiting for a while, they send Jane to get them. She returns with Edward, Bella, and Alice Cullen.
When it is determined that the Cullens will change her, Aro assures him that they should let her leave. In truth, Aro is hoping to persuade them to join the Volturi. Even though she is allowed to leave, he is of the opinion she had to be killed, but does nothing to persuade Aro's mind. When the Cullens leave, he warns them to follow change her soon, because the Volturi don't give second chances.
- Main article: Breaking Dawn
- Main article: Breaking Dawn - Part 1
- Main article: Breaking Dawn - Part 2
- Main article: Volturi Confrontation
Athenodora is Caius's wife. They first met during the time of the Romanians' rule and they began traveling together as a bonded pair. They formed the Volturi along with Aro and Marcus. After Didyme's death completely debilitated Marcus, Caius and Aro realised they were vulnerable to the same devastating blow in their quest for power. Athenodora and Sulpicia, Aro's wife, were from then on heavily guarded in every way their husbands could devise. Though Caius is ruthless, sadistic and abuses his power over the vampire world he is still as devoted to Athenodora as he was when they first fell in love, showing he does value her life and vice versa. Athenodora stays in the tower and the few time she does leave like in Breaking Dawn, he ensures that she is perfectly protected at all times