Why isn't Killua in the On & Off category. At the start of the series, he ripped Johness' heart out out of malice and even crushed it in the manga. He later also mercilessly murdered 3 hunters who simply bumped into him. So how is Killua no in the On & Off category. Although I did only watched the show to the Zoldyck Family Arc so I'm not aware what he does in the future.
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