What exactly is Kurosaki Mafuyu's eye and hair color? The mangaka has always depicted them in a different color. Some that I remember: For hair color; grey, brown. For eye color; blue, grey, brown.
I'm inclined to think that her hair color is grey, as that is the most common coloring, especially recently. Eye color… the only thing I can say is that it isn't blue (if the recent official art is anything to go by).
In earlier chapter the Student Council members were using sunglasses to avoid seeing the Student Council President directly (because seeing the Student Council President directly has some... interesting effect.) How come in later chapters the Student Council members didn't use any method to conceal their eyes?
Maybe it wasn't the Student Council, but just regular flunkies of the President's? In the Student Council Member's flashbacks, it seems Miyabi had other followers, separate from the to-be Student Council, that did wear sunglasses in proximity to him.
Also, the leader of the Yojimbo Club seemed to have no problem speaking with Miyabi without sunglasses.