y did amane/hanako killed tsukasa?well, we do not know that. there are no confirmation nor denying. you might be unable to understand this because of the bad grammar. now now, this is a theory
we'll look into. so on the intro of every episodes you see, tsukasa holding hanako weirdly. or touching him weirdly. i think why hanako killed himself is
because of guilt or wanting to die because of the harrasment. even though tsukasa is the younger one, we think he sexually harrassed hanako. there are a
few of evidence, first is the "let's play how we used to." if i remember that's what he said. second, the act of him, you see "have you schoomed yet?" in the episode 9. (i'm not sure if the word is schoomed, sorry.) he said that to yashiro nene, no. 7's assistant. look at the youtube video "five facts about yugi tsukasa/five things about yugi tsukasa" at the last fact/thing about tsukasa- a trivia, favourite s n a c k ? "amane." we can know more information on wiki page- Yugi Tsukasa.
here is the trivia:
His favorite snack is Amane.[2]
His latest concern is Amane.[2]
What he wants for Christmas is Amane.[3]
His preferred type is Amane.[4]
He wants to spend time with Amane.[citation needed]
He has no comment towards how he feels about lightning.[5]
He is still passionate about doing katanuki, even as a supernatural.[6]
He seems to like painting the wall with blood or ink that comes from a bug.