It satisfies a primal urge coming from the psychological idea of
incorporation, which should make all cock-suckers feel better about themselves! (emphasis added is mine):
An
unconscious process, sometimes termed a
defense mechanism, in which the qualities of another person are taken in, or “in-gested,” through physical contact, and become part of the self. According to psychoanalytic theory, incorporation is the most
primitive means of recognizing external
reality, and the
prototype of instinctual satisfaction. It first occurs in the
oral stage when the infant feels (or fantasies) that the mother’s breast, and perhaps her total being, are becoming a part of himself during the process of nursing. This
mechanism is considered the earliest and most basic form of identification and
intro-jection—the first expression of the child’s impulse to assimilate the attributes,
omnipotence, and later the attitudes of his parents. As he grows, he “swallows them up” psychically just as he did literally during the nursing period.
Incorporation is also considered the earliest expression of sexuality, since it is the first way an instinctual aim is directed toward an object, the mother’s breast. As the child grows,
the sexual instinct is expressed in other pleasurable oral activities such as sucking, biting, and swallowing objects. When he has reached the stage of genital primacy, or
sexual maturity, the oral incorporation impulse is still operative, as indicated by the expression “I love you so much I could eat you up.”Psychoanalytic theory also holds that many of the symptoms of regressed schizophrenic patients, such as voracious eating and “
cosmic identification” (identification with the universe), hark back to the infantile incorporation
mechanism.