If you are playing 0:D stable NPC’s will non change their opinion of you upon death and will treat your new character the same way as if you never died. I.e. friendlies stay friendly and if you got someone angry by trying to steal their chocolate bar you can bet that they will hunt you down and all your future reincarnations for daring to attempt such a thing.
I believe, but am not 100% sure, that on the latest experimental NPC’s do reset their opinion of you after death. Meaning you have to regain their trust if you want them to follow you again.