@MemoriiValentine is exactly right. The PortraitPanel mod displays the non-controllable roommate sims in the panel on the left. Clicking on them only focuses the game camera on those sims, you can't actually take control of them and they are not part of your sim's household. You can actually use the mod to add other non-selectable sims from other households to the panel that way, if you wanted to.
But you can switch the feature off entirely in PP's options if you want. NRaas > PP > Options > Filter > Only Selectable > (change to True).
You can also get to PP's options by right-clicking on the Cycle Portraits button at the bottom of the panel.
