Melanin, Melanoma, and Melanocyte were the three virgin daughters of Diana in Greek mythology. Melanin was the goddess of the darkness before dawn, and Melanoma the goddess of the darkness after twilight. They both fell in love with Apollo, and quarrelled as to which of them should have him. Melanocyte, goddess of the darkness at the new moon, feared that they would kill each other, and appealed to the gods to separate them. As punishment, one of them was fated to always follow after Apollo, and the other to always flee before him, but their fate was that they would always vanish before they ever caught up with him, or he with them.
(The fourth daughter, Melloyellow, is not much talked about in the myths. Possibly she became the goddess of bananas.)