"Read a book for each color of THIS rainbow: Red, Orange, Yellow, Green, Blue, Purple, Pink, White, Black, and Brown. You may double up books for this challenge but not double up colors (i.e. a book that is red and black may only be used for either the red space or the black space). The color must be a majority of the cover."
It's the second category from HRCYED 1.0 that I'm doing monthly (whit the new releases). And as mentioned before, not doubling up. I love to suffer.