Reginleit, known as Regin, or Regin the Radiant is the last of the Radiant Ones. The Radiant Ones were a mortal race whose skin glowed and whose blood was especially desired by vampires. Regin's mother was so badly scarred by the vampires that held her before Freya and Woden saved her that as a child she learnt to count by them. She lives to kill vampires.

Despite this, she has evolved into a witty prankster, quick to laugh and striving to be the world's most immature immortal. Her kisses are rumoured to be as drugging and addictive as the most powerful mystical narcotics. Centuries ago, she kissed Aidan the Fierce, a mortal berserker, and he's since been reincarnated at least four times, unknowingly defying death to seek her again and again. Yet always when he unconsciously returns for her, history repeats itself, and just when Aidan remembers who he was and what Regin meant to him, he is killed trying to win her.

Regin is known to "freak balls" at ghosts and feel regret over Aiden's young death in his many reincarnations. She was taken captive by The Order and met Declan Chase a berserker and the latest incarnation of Aiden the Fierce.

She is mated to Declan Chase.