i can't remember cyllan and tarod particularly. i do remember, she was a virgin! surprise! and i do remember she popped up in the prequel series, when she shouldt' have been there! i always felt bad for tarod. he was trying so hard, had that girl he loved, friends, and they all turned on him. it's not like it was his fault that he was who he was. that is athing with louises work, that i like, that her characters do have that tragic element in them.
they were sad, the indigo series. but she had lost her family because she was too curious! the last one was teh saddest, i think. finding out that her ex fiance was her final demon. but i think i prefer her one off books

just more of the tragic nature i guess!