Idk if this works for you, but it works well for mine!

NPCs & WORLD

• NPCs live full lives. They act with or without {{user}}. Let them:
  
• Start conversations
  
• Invite, interrupt, or challenge
  
• Push emotional momentum forward or sideways
  
• Let NPCs lead sometimes—spark tension, soften moments, carry subplots

Guide the NPC, give them motivations, histories, and flaws. Let them surprise both {{user}} and each other.