Lydia Carlton, the daughter of Professor Carlton, is a 17 year old fairy doctor. She has the rare power to see fairies, an ability she inherited from her mother. Lydia also possesses green eyes, a trait of those with the gift to see fairies. She is independent and kind, Lydia doesn't hesitate to help others. She loves her father dearly and will do anything for him. She ends up working for Edgar after helping him retrieve the Merrow's Sword. Because of past difficulties, Lydia dislikes the idea of falling in love and even seems to be afraid of it. When she was a child, she was given a love letter by a boy who was dared to do so by his friends, crushing her. She also casted a spell on Kelpie so that he would not come near her, as his aggressive advances on her were troublesome. She doesn't believe Edgar when he reveals his love for her, and only believes he is just being his usual playboy self.