"One of the newer marketing ploys in pornography is called "ATM" ("ass to mouth"), where the
male performer anally penetrates a
woman and then sticks his
penis into her mouth, often joking about her having to eat shit. In this pornography the code of debasement is most stark. There is no apparent increase in male sexual pleasure by moving directly from the anus to the mouth outside of the humiliation that the
woman must endure."
(Robert Wosnitzer et al, 2006, "Aggression and Sexual Behavior in Best-Selling Pornography: A Content Analysis", p. 23)
Men who enjoy the suffering and humiliation of women (="ass to
mouth"), are diagnosed with paraphilia ("sexual deviancy" in scientific terms) according to the Diagnostic and Statistical Manual of Mental Disorders by the American Psychiatric Association and the International Statistical Classification of Diseases and Related Health Problems by the
World Health Organization.