I didn't make it!
i'm in the house of Casius Coccadus but when trying to sleep in his bed, i took his pillow without meaning to and now he's trying to kill me. what can i do to stop this?
Try this in the console.
To get a creature or NPC to stop attacking you: select and StopCombat immediately followed by SetFight 0.
Or you could just talk to a guard and pay the consequences of your actions.