What was with the flower imagery when the boy said he'd never run away from him? It gives it a very weird sexual desire angle to it.
My conjecture is that Okaya (the main villain & antagonist) "fell in love" in a twisted way for Nagure (the deceased son and catalyst to the whole story). Like, Okaya is clearly a psychopath. It helps to think similarly like Joker and Batman where people, stories, fans, etc. argue that Joker's true-love is Batman in the sense he gives him something unique.
My conjecture is that Okaya must have been raised and always is surrounded by Yes-Men, Ass-kissers, and Brown-Nosers. To him, he's grown up learning that people are simply lickspittle tools to an end and not unique individuals with their own beliefs, wants, and needs that matter. Everybody uses everybody and everyone is trying to get something. I mean, pay attention to the conversation Okaya has with the fat-boy: he thinks friends simply are allies. However, businessmen can be allies; "The enemy of my enemy" can be an ally; mercenaries can be allies; etc.. So he doesn't really understand what friends are and are simply just another word for allies... which mean they're just Yes-Men, Ass-Kissers, and Brown-Nosers.
Meanwhile Nagure seems to be the first person who stands up to him and isn't groveling before him to get something. Not even willingly doing what Okaya want to have him stop the pain. He's uniquely and perplexingly defiant against Okaya because of his own beliefs and moral-code. It seems for the first time in Okaya's life he's come across someone who's actually uniquely different and entertaining (compared to his whole life with the constant Bootlickers and people he can easily step-on). So because Nagure was something completely excitingly different in his, from Okaya's POV, monotonous life - Okaya "fell in love" with Nagure ("You were depressed when Nagure died... You aren't really there with us when we hang out... You got mad af when Kowase talked about him [like he was your own twisted sick treasure no one can have let alone use Nagure's name]").
That's my whole two cents.
Here are my predictions:
- Okaya will actually "fall in love" with Maria like he did with Nagure. He's finally found someone after Nagure who's going against him legitimately and Life is entertaining again.
- Fat-Boy will probably figure out he's a disposable-tool to Okaya. I think his arc will be the most different: in the sense I think he'll try join the killer (Maria) against Okaya in an attempt to at least save his own skin (won't work).
- Fat-Boy's punishment will be food/eating-related. Like 99% of the time we see him he's always eating and his type of bullying against Nagure most of the time probably was food-related (like taking his meals).