He is introduced in Dark Fire, where we learn that he witnessed a true vampire killing his fiancée. He tries to help Tempest Trine to run from the Vampire Hunting Society, thus putting him on their hit list. He meets, and marries, Lisa Wentworth, sister-in-law to Dayan's lifemate, Corinne Wentworth, in Dark Melody. He nearly dies trying to save both women. Barack gives him blood, tying them together and saving his life. Cullen chooses to keep his memories, and his new family, in order to protect his wife.