It might be an actual compulsive/addicted condition:
The phenomenon didn't have a name until 1983 when psychologist Patrick Carnes published the influential book, Out of the Shadows: Understanding Sexual Addiction. Prior to that, the behavior was described as "hyper-sexual arousal." In short, the term "sex addiction" is used to describe a pattern of frequent, progressive, and often secret sexual behavior, even when the behavior jeopardizes a person's time, employment, financial stability, relationships, and reputation. While often conflated with adultery, sex addiction does not necessarily mean cheating—or even intercourse. Rather, it can manifest as a dependency on pornography, masturbation, phone or Internet sex, and other related behavior.
The culture constantly suggests to us that there's no such thing as "too much sex." But of course there is. Anything in extremes is most likely to be very bad for you, and the easy (and secret) availability of Internet pron can't help.
I have always wondered if watching a lot of pron would make a person unable to actually enjoy sex with real humans, imperfect and equipped with personalities and needs as they are. This links to the worry I've written about before: That heterosexual teenage boys might acquire their ideas about real sex from pron and that this would then be expressed as the way heterosexual teenage girls are supposed to behave. It's a worry because so much pron is focused solely on the enjoyment of the male actors.