- The prohibition against complementary-color relationships makes a lot more sense when you take two other facts into account. First, it's established that if you can see a color naturally, you're immune to the magical effects of that color (greens can't be affected by the druglike green shades, for example). Second, the Mildew, the government's secret execution method, is caused by an odd green-red shade. If a Red and a Green were to have a child, there is at least a chance the child would be immune to the effects of the Mildew color.
Fridge / Shades of Grey