Important Non Player Character.
For use mainly in various Video Games or Tabletop Games, and all else related.
The goons you fight and kill off are NPC
s, while the recurring Quest-Giver or the PC
s father would be the INPC
GM: So I created a few characters for the campaign today.
PC1: How important are they?
GM: Just a couple random NPCs as workers for this INPC I created.
PC2: Oh boy, someone who we'll see more than once!