Evanna

A "witch" with many powers (who takes great offense to anybody who calls her that). She normally wears ropes instead of clothing. She is Desmond Tiny's daughter, Hibernius Tall's sister and Darren's, and Steve's half sister. Evanna has the ability to breed faces of vampires onto the backs of frogs, and the faces are one of the only ways to see an image of a vampire (vampires can't be photographed but they can be painted or drawn). She is half vampire, and the only one born a vampire. She was the only one because vampires are sterile, but evolved from wolves. Desmond Tiny mixed vampire and wolf blood to create Evanna and Mr Tall. She is the only entity who is able to carry a vampire/vampaneze child. Later in the series She becomes pregnant with twins (each one one third vampire, one third vampaneze, one third herself), the fathers being Vancha and Gannen, as part of a deal with her father to help Darren get to Paradise. She is also the one responsible for Mr Creplsey's trademark scar (see Larten Crepsley). source: Wikipedia