by all rights hidaka should win. it's human nature for the boy to like the girl following him and changing to fit into his life, human nature for a girl to dislike the reverse, the boy looking up to her and being a kind doormat for her. ofc there's more to these characters than that, but that does summarize it.
on the other hand.... boys are pretty dumb and only figure that stuff out after it's too late. i wish i could go tell young cksn.