Ghouls with black eyes?

[Madifishy]

Ok so this question is less of an "essential gameplay" question and more of just something that has had me wondering.

After hundreds of hours of gameplay, I came to the realization that some ghouls have completely black eyes (like Hancock), while others have normal eyes that are just incredibly bloodshot. I've played the game for a long time, and I don't think I've stumbled upon any explanation as to why some ghoul's eyes are black and some are just bloodshot. Or if there was an explanation, I overlooked it.

Is there a reason for this or a story behind it? Or is it just an added detail to give the ghouls variation?

Again, not a crucial question, just something that has had me wondering. Any ideas?

(Note: someone told me that Hancock's eyes may not be completely black, and that his pupil's are just extremely dilated, to the point that his irises and the whites of his eyes are impossible to see. Don't know if it's true or not, but gives me something extra to think about)

[Frosty]

Visual variety I supposed. Ghouls vary a lot within the lore since the varying stages of "ghoulification" from human to feral aren't really well known.

[Minty]

I think it's one of those "varying effects of radiation" things. But yes, there are ghoul eye mods.

[Nish-Ki]

They don't have eye brows, so their face's blank expression always looks sad :[ , I think their eyes serve as something to add character.