So, basically, I'm making this topic because I've barely seen stories/comics that approach shitheads from the angle of it being a treatable mental illness/disorder without making it a bleak excuse for more yukkuri suffering.
Which is a shame, because I think it actually has potential as an interesting setting, and I was thinking of
potentially making my own story about it.
I see shitheadedness as a mental illness like 95% of the time, because 95% of the time it doesn't actually serve the logical purposes that normal meanness/selfishness does, and only ends up hurting yukkuri and making them more self-destructive. Yukkuri are weak, needy, social creatures that don't have many traits that back up the ability to be mean and get away with it. Even a yukkuri that wins a fight would probably hurt itself or waste energy, making itself more vulnerable. Even shitheads who can manipulate others usually lack foresight and can only think about themselves, so the whole thing will blow up in their face soon enough. Therefore, this setting is assuming that a normal, mentally healthy yukkuri should only be mean when nothing else worked.
Anyway, what consequences could be caused by the existence of anti-shithead medicine? I'm thinking specifically if it actually has a high success rate, since the point of this idea isn't just suffering. There could've previously been an argument that killing a shithead was merciful, even doing the yukkuri gene pool a favor, but now there's demonstrably a reliable and humane alternative.
I was especially thinking of what the consequences would be if the anti-shithead medicine was unexpectedly cheap and easy to get, and the overall fixing process was pretty easy. This way, it actually does matter and have a huge impact for the whole population, and not just exceptionally privileged, skilled, or lucky people.
The main idea for that I had was that it turns out to be just be a relatively simple orange juice based formula. If you just add a small dose of a core-harming toxin to orange juice, the orange juice will now have the chance to heal the yukkuri's core, which it usually doesn't. The juice will immediately fix whatever damage the toxin causes and "rewire" the core to be better than before, improving the yukkuri's mental health and cognition. This would also be paired with some therapy and training, but the medicine would make the process so much easier that anyone with a decent amount of time and patience can do it. The orange juice will always heal the damage as long as the toxin concentration is low, so it is also pretty difficult to be careless and overdose the yukkuri. (Again, this is not supposed to be an easy excuse for suffering). To do that, you'd probably have make the medicine from scratch and add way too much toxin, which would only be possible for really stupid or actively malicious anons.
Pet shops could react either positively or negatively. Now they can sell just about any yukkuri as long as they use the formula, or sell the formula so people can do this themselves. That sounds like pretty good news for them, and yukkuri ownership would probably increase by a considerable margin + yukkuri would probably become more sympathetic and pitied when people realize they can be rehabilitated and redeemed without a gigantic investment of time and money.
On the other hand, now yukkuri have been leveled out to a certain extent. There's still the rare and special varieties, but now nearly any yukkuri has the potential to be a good pet. The formula would also have to fix and enhance intelligence and social awareness to the degree required for the yukkuri to be sufficiently kind and obedient, after all. Genes and pedigrees for behavior and intelligence alone will become much less important, which could potentially have a big impact on profit and how things operate. The system could be changed so much that some things could actually be bad for the pet shops now, so they might retaliate or try to control it in certain ways.
Also, if wild yukkuri ever discovered that humans know how to fix all their shitheaded friends and family, how would they respond?
Like there could be a mother Reimu or slave Marisa coming to a house, but instead of doing typical shithead home invasion, tearfully tells the human that she'll do whatever the human wants as long as they fix her awful, dirt stupid, selfish family so they can take it easy.