What we saw in the first chapter wasn't the worst of it; in the two years since that event, Hiro did something far worse -- something like crossing the Moral Event Horizon, perhaps. Something that would make our Designated Hero much less sympathetic if we knew the truth. The Time Skip, therefore, is meant to hide this information until The Reveal in order to make it seem like less of a Shocking Swerve. * * Like maybe he killed Hikari.