He’s never been particularly afraid of the light until now, when he knows he’s done something worth hiding. And it almost feels as if his shadow has taken up a permanent presence behind him, so that he misses something each time he whips his head around. It’s become the only thing he’s afraid of, so much so that he tries to become one with that which haunts him.
To him, the sun becomes a hideous being, and so he avoids it like the actions of the condemned. He’s not sure who’s looking for him, but he’s certain someone is watching, and someone is interested in knowing what he’s done so that justice can be done.
He’s not ready to confess, so he carries denial like a secret to be kept, only to break his own rules in the end.