Alyssa is one of the Vampire Kings, as well as being the only female. She's still a Vampire King, though, becuase "Vampire Kings and Queen" doesn't have the same ring to it and "Vampire Monarchs" is just silly.
Alyssa was born as Alice to the air spirit Zonda and the mountain spirit Balvan. Her body was shaped by Balvan to look like a combination of himself and Zonda. At first she was only a stone body, then Balvan added a piece of his essence but only created a small entity in the astral. Then Zonda placed some of her essence into the child, and she woke up. She lived out her days with her parents until she was slain by some unknown means. Swayne offered to bring her back and Balvan agreed. Balvan swore an oath of service to Swayne, but he was horrified to find that Swayne had turned Alice into a vampire. Spirits cannot break their oaths, so Balvan still serves Swayne to this day.
Alice somehow found her away around becoming Swayne’s personal vampire BFF and carved out a piece of territory for herself. She now rules over Verandi’s equivalent in the Shadowfel. Little is known about her practices other than what being a vampire would entail.
The Dead Wars
When the vampire kings invaded through a portal into Ytarran lands and were counter invaded, Alyssa played a large part in fighting the Ytarrans, getting the rather ironic name “The Crone” for her trouble. This nickname is so comical because Alyssa, in fact, looks like a 12 year old girl.