Perhaps because he was very young, he couldn't bear losing his brother all of a sudden, so he created a Tsukasa in his mind actually believing that it was him, and for some reason he killed THAT Tsukasa and then himself. After all he is being punished for something and it cannot be for killing a being that doesn't really exist, if he didn't kill anyone then he must have killed himself. Though this is what I think.
Maybe the entity who took the child Tsukasa is the teen Tsukasa pretending to be the real one. Bc, even the spider sensei knows tsukasa's existence when hanako was alive. So, maybe the the entity took tsukasa's identity, and hanako knew he wasnt real so he killed him?
I kind of wish that his brother was a cute guy that died young & that the person Hanako killed was some mf entity that was obsessed with him
Right?! Becase lets be honest small tsukasa is an absolute dear and he seems genuine, He is so adorable when he kept bumping into things so im hoping that maybe your correct
Because*
I'm in tears and confusion, if Tsukasa sacrificed himself for Amane then who was the other Tsukasa that was abusing him?? Does Amane know??? Gotta wait another month to find out ┗( T﹏T )┛