Lisa Burkett

Lisa Burkett was a witch who had an affair with Albus Dumbledore, when he was married to Sheila Rookwood. The jealous Sheila killed Lisa, and she became a ghost. When Albus fell in love with Minerva, Lisa became jealous, and therefore she tried to kill Minerva, but she failed. The ghosts of Dinah, Anita, Lisa and Cassius kidnappe Sheila when she tried to kill Harry Potter and Hermione Granger. The four ghosts want to kill Sheila as revenge for her killing them in the past, but Sheila manages to escape.