NPCs coming into apartment and becoming part of active household?

[Nightshade2010]

I created an apartment on my sims 3 in Aurora skies. I did enter the codes to get the special orbs to make npc players rooms private and clicked on there doors to generate a npc players for those rooms. I put a public orb in the hallway but no robs of any kind in my sims apartment. When the npc characters showed up they became part of my active household?? I deleted them and let them die off but new ones the next sim day show up and once again become part of the active household?? I did use codes buydebuy and buybuildinginbuild false (don't remember exactly how it went but that's the codes I used)