Astaroth
One of the seven Satans. "Astaroth" actually has two souls in one body. Astarote is the female and Astarot (not too sure of the spelling here) is the older brother. This happened because of a failed project to create another being like Adam Kadamon. Lucifer helps "seperate" them. When one is in the main body of Astaroth, the other's mind goes into the body of a snake. When Astarote is the snake, she is white, while her brother becomes the black snake. When one occupies main body the gender switches accordingly. Astarote is in love with her brother and eats children so she can fill her stomach and make herself feel pregnant with his "child". She tries to turn Kurai into her "baby", but is killed. With her last remaining strength she turns herself into her snake body and dies. By doing this she hands over the main body to her brother so he can live on normally without having to change into a snake.