Ivan

Ivan Kirst is a pureblood demon, the Prince of Darkness, Rennai's secret tormenter, and one of the four protagonists in the Nightmares Series.

Ivan was the result of an affair between Kevin Kirst and another woman. Refusing to care for his bastard child, Kevin left the baby to die in an alley and assumed a new identity as Isaac LeGrangine. Unbeknownst to all, the woman that Isaac/Kevin had sex with was Wrath in disguise. Incensed by the cruelty, she signed a contract with Lucifern and had the baby turn into a powerful demon, who started calling himself Ivan.

Through the contract, Wrath commanded Ivan to drive his father and new Peter insane before causing the eldest to slaughter the entire family. However, he spared the youngest upon discovering they were not biologically related.

However, Wrath's decision to give her son sentience proved to be a mistake when he realized she would continue to use him to curry favor and enact personal acts of revenge. Ivan then overpowered her, escaping from her control, and assumed himself as the ''dark prince. ''With his newfound freedom, Ivan settled in Magnolia, and continued to wreak personal havoc.