I tell myself I will resort to the 12 gauge in a situation like this, but I am a big fan of 7.62 in large quantities and the scatter gun only hold 6. AK is shorter and more maneuverable indoors that the pump gun. No disputing its effectiveness in dispatching nerdowells.
Aquila home-defense 12 gauge rounds and Kel-tec double magazine bullpup pump-action shotgun. Total loadout is around 24. The Aquila rounds are (as I recall) an inch and three quarters long. Shells come both as slugs and shot.