All humans have lust that strong, there are different types of lusts and desires most notably the desire to make love and the never-ending lust for power or money, what most people won't tell you, especially governments and scientists, that all humans share the lust to kill which is greatly connected to the lust of power (authority), governments have been killing people left and right, and when they do it it is right and good, but when someone like me does it is the worst.
Killing and murder are our true nature and it is what made us evolve to this point right now, if there weren't any threats to humans from other humans in the past there wouldn't be anyone who naturally becomes scared when facing a stronger enemy, it's an evolution thingy where we are scared of the strong because they might kill us even strong humans, humans used to kill and eat each other as a survival nature from the beginning of time
That's what Maru realized when studying psychology, with revenge and pity and self-hatred Maru became maru unstable day after day as a newly graduated high school student, at the age of 16, he finished early as a result of getting into elementary school early.
Maru hated humans and saw himself as a piece of shit, he didn't want to be the prey anymore he wanted to be the hunter, he got sick of always being the bullied one, or the one who was at the bottom of the ranks in anything.
Even Maru then didn't believe what he thought, he thought that he might need a therapist, he felt like there was something wrong with his mindset, he felt like his imagination of killing his father and his bullies was wrong, he started asking himself, am I the bad one, do they deserve death? Their sins aren't that bad, right? It was not like them stabbing him with pencils would kill him, then he started to refuse the urges to kill them, till that one day arrived