I think this is a real insight.
Shiroi karasu (白い鴉) : this is the first time I have heard of this expression but it is very definitely a common theme in a couple of sites that mention it: I think we need native language input to unravel the exact reference.
Googling the term I come across a track by kagerou called Shiroi Karasu which I have just seen it features the line which seems transparent enough:
"itsumo no kaeri michi hitori arukinagara"
so the inference seems obvious: someone who is outside. Unfortunately the guy? in the song is alone in apparently a routine, boring, everyday way!