Who is Christabel LaMotte from Possession: A Romance and what is their importance?

Christabel LaMotte is a little-known Victorian poet. She is a petite woman with light hair, large, even teeth, a pointed chin, green eyes, and very pale skin. Christabel is not exactly beautiful, and her face has very sharp features. Christabel dresses elegantly, if not in the height of fashion. She lives with her lesbian lover until she has an affair with Randolph Henry Ash and bears a child as a result of the affair. Her lesbian lover commits suicide, and Christabel ultimately lives out her days as a spinster with her sister and family. Her child is raised by her sister as if it was her own.