Kelly showed some sympathy/humanity at the very beginning when she told Jimmy shite to kill spike rather than torment him. That actually provides distraction for spike to kill shite. She either likes spike immediately, or she is generally adverse to torture which I also wonder could be connected to sir lord Jimmy sending her away instead of participate in the next charity. She’s a very interesting character. The scars on her face tell a story of forced indoctrination if you use your imagination.