From the black cat to the black veil, everything associated to darker aspects is looked down upon. In many traditions, black is linked to mystery, secrecy, and even danger, and it is said that excessive use of black is will create an imbalance of energies, drawing in heavier powers toward the person.
Black cats, for example, are seen as dark omens across beliefs, and when describing something as eerie or filled with horror and fear, the background of black is used.