I'm having an issue in my game that'll have my screen half black, glitching everywhere when I come close to certain sims that have on something that is a bad clothing item I guess? When I had this issue at first I took out all of my custom content and mods, and decided to make a new Sims 3 Folder without any custom content or mods, and the problem still exist after that. I then decided to use nraas dresser in my game to see if its an invalid clothing item, reseting everything with MasterController as well and it still happening oddly. I went to cas to see if that can tell me anything else, but no, just a demonic entity, and the cas is showing up as the sim being a pet. I heard it can possibly be a gpu issue? Could my save just be corrupted as well? I'll keep testing in the meantime.

Does it happen if you make a completely new savegame in a completely different world, or is it happening in all worlds/ saves?

Does it happen if you drag your Documents/ Electronic Arts/ The Sims 3 folder to the desktop, and run the game to make a new folder?

I've had that happen when regurgitating Sims from an old save. Not 100% sure what causes it, old cc that's not in game anymore, world cache, who knows, but those sims are done. I've spent a few hours trying to fix them with no luck. You can try and if you find an answer, please post it. My advice is to just remake them, or reimport them from your bin, and be done with it. If the bin Sims do that, delete them and start over. If you can click on the Sim, you can use Nraas MC to transfer their inventory to the clone, and reestablish relationships.