I got annoyed with an npc early in the game and cast a curse spell on them, thereby aggroing them. Diddnt wanna kill him so i just ran away and carried on.

Turns out the character is key to the story and i need to to talk to him to progress in the story. Is there any way I can de-aggro a character artificially or whatever? He wont die because hes a key character and just heals up all the time.