Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.
An Ajin who grows a new head isn't really a copy
This is based on the assumption that the original consciousness can't be transferred to the regrown body. Except, Sato's teleport tricks show separated body parts are still linked together - the fried hand didn't regenerate until the body was destroyed elsewhere. More definitively, in the base invasion, Sato regrows from his arm and remembers seeing Kei, even though the arm had been separated before that. If he was being copied, you'd expect him to only remember everything up his arm being cut off. Memories can transfer, so there's no reason consciousness can't either. Presumably Sato was just messing with Kei's head.- Or maybe he just hasn’t thought about it long enough to realize it. He probably doesn’t care enough to, given he has taken advantage of his own consciousness “dying” to sneak through security before.
Kaito the Ajin?
There's probably some secondary way of telling who's an Ajin that invalidates this. But wouldn't this just be a kick in the teeth?Like I seem to recall him at least sometimes seeing BG when their hidden, so you'd think he'd see his own if he had one.On the other hand A) I have no idea if those can show up for an Ajin that never died before and B) considering that if no one knows he's an ajin he is infinitely safer, maybe its hidden cause its safer to let Kai get hurt. To an ajin death is infinitely less dangerous than discovery. Does the U.S. have Ajin refugees applying for asylum?
If Japan and the U.S. are so diametrically opposite on Ajin welfare, its safe to assume that people often flee from one to the other.Some might even emigrate who aren't Ajin simply because they object or because they realize their future children could be Ajin.This goes for all the other countries in the world with poor Ajin policies and humane policies respectively.Heck, if there's any countries that give Ajin full autonomy and rights with no restrictions? Then they're probably the ones getting all the Ajin.