as someone who has read the novel, is autistic, and has also lived with an actual psychopath (my biological father), he is definitely NOT autistic but is in fact a psychopath. Autistic people at least can feel and understand guilt and remorse when they do something bad (at least most of us can, like hurting a person or animal), and we do actually feel emotions like happiness, sadness, etc. I mean we know from kmiyc that he lied about Chase sleeping with Alex, Grayson’s dog, while Chase was in rut, purely because he was interested in how Chase would react and he doesn’t see the big deal and what’s wrong with having sex with a dog, he literally cannot understand why everyone is “making a big deal about it”.In the novel we discover that Grayson genuinely doesn’t feel anything naturally, he’s a true psychopath, not even feeling bad when the results of his direct actions cause harm to those he loves (this is a spoiler but he once poisoned koi intentionally because he wanted to see if it is really true that koi can’t smell or taste anything, which he can’t, and felt no remorse nor understood why his actions were bad even as he watched koi very badly suffering the effects of the poison, and Grayson doesn’t have any dislike for koi as he says how much he loved smelling koi’s scent when he was younger and he was quite close with him before he poisoned him). Grayson shows genuine psychopathic behaviour, all the behaviours he’s learned up until now he just wears like a mask, he doesn’t actually understand them or feel them, he only knows he needs to show them when interacting with others so he doesn’t become a social pariah, even though he doesn’t actually care about what other people think of him. Psychopaths will often learn how to perfectly manipulate others into believing that the perfectly curated image of themselves that they show to others is who they truly are, even if they are actually the complete opposite of that image, especially since most psychopaths are also narcissists, and they will learn how to perfectly imitate the behaviours of non-psychopaths in order to blend in and be well liked, and unlike autistic people who struggle to understand social cues and behaviours because of the way the autistic brain is wired and works and so their imitation of social behaviours and cues can be a little off and doesn’t come off totally natural, for psychopaths they don’t have that difficulty with understanding social cues and behaviours and so don’t struggle with imitating them. The perfect example of how psychopaths are often able to perfectly, seamlessly blend in with others and do so very naturally is Dexter from the tv show Dexter, his imitation of sincerity and social behaviours is flawless and comes off extremely natural, he doesn’t slip up nor does the imitation make him feel drain of energy the same way it does for autistic people to imitate those same behaviours
oh yeah they’re all a bit messed up in their own ways, part of it is genetic as we know Ashley’s father Dominic was a CERTIFIED psychopath in the worst way possible, who did not have loving and caring parents growing up who tried their hardest for so long to teach him right and wrong the way Grayson did, and then poor Chase is messed up because he was treated so badly for inheriting koi’s soft and bleeding heart and caring so much while surrounded by older siblings and a father, Ashley, who were cold hearted and mean to him because he has always been such a soft and gentle soul despite being a dominant alpha, so he was expected to be cold and uncaring, the best thing to ever happen to Chase was Josh coming into his life permanently and teaching him that he can set boundaries with his family and not feel bad about it, to stand up for himself and not let his family abuse him.

They say he's a psychopath but he lowk just seems autistic to me lol