He likes talking to himself, he said it "out loud" at the point he wasn't clearly within her immediate hearing range; doesn't really affect the story I guess.
Regarding his haircolour, it's not necessarily that his hair is bright green or anything fancy like that; but on the colour spectrum it's clearly edging too far into the green area to really be considered a proper naturally blonde colour.
I'd call it a haircolour on the verge of realism, or something.