that time I got reincarnated as rui

Prologue

A boy of the age of 14 was what everyone called an otaku,if one asked him who was his favourite character he would say "rui lowermoon 5"in the anime demon slayer.
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This boy was named Hiroshi.Hiroshi always wanted to kill but he never did or else he would go jail.
He always thought that he and rui was the same both of them were weak since birth and always wanted to join other kids to play with them.
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He had always wished to be like one of those novel that the Mc got transmigrated into a world but in his case he wished to transmigrated as rui.
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He thought that when that happen his first goal will be to raise through the ranks because canon rui had potential to be an uppermoon but he only thought about creating a family.
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His other reason for being in the upper rank is so that he could reach upper 2 and because he wants to be kokushibo's lover because he always have loved him, or atleast be someone kokushibo would kill for .
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Author's POV

But little did he know that his wish will be granted.