I believe what Family chioce says....It has to be made as unpleasant as possible for them till the day they die and go and go to hell.
Killing them would be nice but I do think it is the easy way out for them.
We have a murderer here who gets constantley bashed and when he heals they just do it again - now that is justice...Apparentley he is so paranoid now he wont even eat his food because he thinks someone is poisioning him...Love it!!!!!