The bluest eye

… hmmm,,, translating a metaphor literally, tends to, well, lack the idea of 'depth' (as in a well thought out idea).

What is the book about? Is it about 'blue' eyes, or that a metaphor for something else, like "Behind Blue Eyes" (by The Who)?

I think then, your cover image won't mean 'blue eyes' literally, and thus you won't have to try filter blue into eyes, because the metaphor might be something else.

hauting image that -- just wondering why her pupils are blue