GTA V - Trevor & Franklin malfunction

SEIZURE WARNING: The geometry rapidly flickers in and out of view. If you are photosensitive, DO NOT watch this video for any reason whatsoever.

How I got this glitch; while playing as another character, I caught Trevor doing some "random things", and then....he walked around for a bit, then this literally happened out of nowhere.

Given the circumstances, I'm betting this glitch can happen without mods of any kind.

Also, Franklin is glitching out because I'm playing as Schwi Dola while using Franklin's character ID. I assume the game can't quite figure out what to do with Franklin's model under these conditions. In this case, mods ARE required. :P

The flickering BSP/geometry may be an unfortunate side-effect of Franklin's mutated model.