1. Indulgence in sensual pleasures; scandalous activities involving sex, alcohol, or drugs without inhibition
Does this mean that a life of debauchery is just as valid as a life of piety? Yes. But, really, when the length and breadth of human religions allows for both chastity and licentiousness while still being pious this shouldn't be a surprise for most people. Sure, it has been a while since temple whores have had popularity, but they have existed in the past, and humanity may well see them again. It seems that any time one group defines sexual morality there is a group somewhere providing an alternate definition.
The universe doesn't care what you do with your life -- only that you live.
What is there to prevent you from living a life of debauchery? Clearly nothing, as we see plenty of people enjoying such lives every day.
Realistically, though, lives of unfettered debauchery tend to lead to hurting a lot of people. It is not in human nature to hurt others needlessly, (most people tend to primarily hurt themselves), however it is even less in human nature to allow friends to be hurt needlessly. (To paraphrase the Christian Bible, "Vengeance is Mine, says the BFF.") Those who would use other people will eventually suffer repercussions for their behavior -- after all, you can fool most of the people most of the time, but not all of the people all of the time.
Note, though, when I speak of a life of debauchery I'm speaking of a self-centered life of excess. The implication with the term "debauchery" is that there is a moral or ethical common-ground and that whatever that common-ground is, debauchery goes below it. This is quite different than ethical hedonism. You can love the pleasures of life while still loving and caring for the other people in your life. In truth, it shouldn't surprise anyone to hear two hedonists complaining about some of the choices of a mutual friend and how that person has slipped from ethical hedonism to a simple life of debauchery.
Some might confuse debauchery with a life of orgies and free-love. In truth, some folks find open and/or polyamorous relationships work well for them. These relationships might be confused for debauchery by some, but when relationships are based upon love and communication it should be clear that they are very much not debauchery.
Now, if a relationship is one-sided and based upon either pleasing only one party or it involves degrading or debasing one partner then it bears a lot in common with debauchery even if the relationship outwardly looks like a typical monogamous marriage. Do you want further proof? Add a video camera that only one member of the relationship knows about. This instantly raises the bar in how one-sided a relationship is, but I argue that if the only thing that is missing is the camera, then the marriage may still be thinly veiled debauchery.
For another example: I was once told quite matter-of-factly that "not everything in a marriage is consensual." I was appalled, particularly when she added, "You'll understand after you get married." I'm married now. Rape within the context of a marriage is just as abhorrent to me as it was back then. At least most single-people who opt for a life of debauchery do not need to stoop so low. Sure, they may manipulate, the other party may know it was a bad idea (both before and after), they may even explicitly set out to seduce someone's spouse, but what happens is consensual at the time.
This is really just to make a point. The universe is quite content for you to have a life of debauchery (though you'll probably be happier with yourself if you opt for ethical hedonism instead), and if you do really want debauchery, you can still have that while outwardly keeping a monogamous heteronormative lifestyle.
Now, in the next part, I'll move on to talk more about personal meaning.