Gregor

Gregor was a French Master vampire.

Abduction of Cat
Like Mencheres, Gregor had the ability of precognition, although his ability was comparatively less precise. When he had a vision of Cat Crawfield with pyrokinetic powers, he decided to find her so that he could control such powers through her. When Cat was sixteen, he found her and used his powers to make her mother think he was an old friend. Gregor then took Cat to his home in Paris and convinced her that because of her half-blood status, there were many other vampires, including Bones, who would want to exploit her special status, and that Cat needed Gregor to protect her. When Cat developed a crush on Gregor, Gregor had her bind herself to him in marriage in the name of her protection, despite Cat's reservations and reluctance. Just as they were about to consummate the marriage, Mencheres arrived and intercepted them. Mencheres rebuked Gregor for using his power of precognition for selfish purposes and dragged the terrified Cat away, erased all her memories relating to Gregor, and returned her to her home in Ohio where she resumed her life. Gregor was subsequently imprisoned by Mencheres for twelve years.

Return and attempt to reclaim Cat
Around twelve years later, Gregor was freed with discreet help from Marie Laveau, a ghoul whom he sired. He began to appear to Cat in her dreams, hoping to use his dreamsnatching abilities to teleport her to him in her dreams. In her dreams, he told her that Bones was not her real husband. When Cat realized what was going on, she began taking pills to help her skip REM sleep. Eventually, Gregor attacked the house where she was staying. During the battle, Cat was locked in a closet for her safety, with video screens so that she could see what was going on outside. However, Cat thought that Bones and his forces were losing the battle, unaware that there was an ambush of mercenaries waiting for Gregor's ghouls. Wanting to protect Bones and the rest of her loved ones, Cat offered to let Gregor dreamsnatch her if the attack would stop. Gregor agreed and teleported Cat to him in Austria.

After Cat returned to Gregor and recovered her lost memories by drinking his blood, she still wanted to return to Bones, so Gregor was obliged to go as per their agreement. Upon returning to Bones, Cat and Bones had a fight which resulted in a temporary split, with Bones going to New Orleans to speak with Marie Laveau. Gregor followed Bones to New Orleans, but as Marie closed the French Quarter to all undead visitors, he was obliged to remain outside the city. Instead, he sent his human servant Cannelle in with a mission to seduce Bones and bring him outside the city where Gregor could kill Bones. But before anything could come of his plan, Cat airlifted Bones out of New Orleans.

Shortly after Cat and Bones reconciled, Cat changed over into a vampire, rendering Gregor's ability to dreamsnatch her useless, as his ability had no effect on vampires. In retaliation, he dreamsnatched her mother and changed Justina Crawfield into a vampire. Cat and Bones, along with a few other allies, raided Gregor's house while he was away and recovered Cat's mother. During the raid, Cat found herself demonstrating pyrokinesis by burning up the house and Gregor when he returned. At this point, Bones grabbed her and flew them both away.

As soon as Bones had discovered that Gregor was invading Cat's dreams, he challenged Gregor to a duel to the death. Gregor accepted the challenge following the raid. Despite Gregor being older and more powerful than Bones, the duel was a close one, and Bones eventually gained the upper hand. However, Gregor's final silver knife was equipped with a special function that allowed it to secrete liquid silver when he pressed the tip of the hilt. Because Bones was Cat's sire, she felt some of the pain as the silver spread through him and knew that something was wrong. In rage and desperation at seeing that Bones was going to lose the duel, she inadvertently caused Gregor to combust in flames and die. When Bones revealed Gregor's deception and Cat claimed that she only interfered when she knew that Gregor had cheated, the Law Guardians who oversaw the duel acquitted them both.