*manhua sorry
and also the way that wang yi is behaving (like he's mostly apathetic and only express emotions because he should blend in) is because he was just a system (S0 explains that the human emotions of a system are nonexistent no matter how hard they try to pretend to be human)
S0 stated that Wang Yi was chosen as a villian not necessarily because he was a villian but because of his capacity to understand them. He definitely has emotions though he may not have before, which might explain his apathy and struggle to express and identify his emotions. He did something that made him human, it might be possible that he had developmental problems in the social and emotional departments because of this. He had to build human aspects of the personality and mind from ai that might not be fully sentient. It seems system Y developed some sort of attraction to his host and recognized it as affection (false or not) and led him to do something he was NOT supposed to. It seems the two of them made some sort of plan that went awry and led to system y's death though outside of being erased by the top ruling being of the novel world and transmigrators.
I knew wang yi was a system like S0 from the start holy shit.... it explains a lot because in the fragment memories of qin xian (the legendary villain) it shows that wang yi is a system just like S0
and maybe the story went like, system y (wang yi) did something bad and get resetted, leaving villain qin xian and drove himself mad and split himself to fragments, and now system y became a normal human but with 99.9% villain genes (like at the start) it's because he was a Villain guiding system so naturally the higher up deem him as a Villain candidate. and now he had to be on the opposing side with protagonist qin xian
and to think about it, protagonist qin xian has a lot more villain quality despite being the protagonist from the very start
I've been rereading this manhwa more than 10 times just to notice every little detail (that's how crazy i am dawg)