As a Known Enemy (слэш)

He has no idea what makes him do it. It just seems that today, of all days, in Kentucky, of all places, to collide with Harry Potter at a goddamned gas station is an occasion to be memorialized.
In which Snape and Harry take an angsty road trip across the U.S., with a side of vigilante justice.
(Very slight Justified crossover, no prior knowledge necessary.)