[quote=@MyCatGinger]
[b]PLOT TWIST:[/b]

This is out of the complete blue, but...
Nobody really knows what Shou's natural hair-colour is.
Since it's all dyed silver.
...and when I have to find a picture for his brother (probably a total NPC who doesn't even show up, but his name is Yuusha)...
...WHAT ARE YOUR HEADCANNONS FOR HIS NATURAL HAIR, GUYS?
[/quote]

Well, I'm going to be boring and realistic. Assuming he is Japanese by blood... black/dark brown.

EDIT: Or, assuming he is anime by blood... electric green.