How do you delete/remove Sims without a home?

@Advercius You could also use TestingCheats to change that other Sim so they don't look like your Sim anymore. With testingcheats on, just shift + click on that Sim and select Modify in CAS. You could change their hair and clothing to something different and give them a new name. They'd still sort of look like your Sim but maybe not enough to notice unless you looked really close.

If you also use the cas.fulleditmode cheat you can completely change their appearance, age, gender, traits, everything!