My 2 cents on this.
Let’s say that we are talking about a single male, I wonder if the real issue behind the question is something like this:
One’s kama raga (in this case sex) is particularly strong that one needs to seek a relief through:
(i) Going where prostitution is legal to relieve oneself.<br /><br />
(ii) Having sex with another consenting, non-attached adult who is not one’s stable partner.<br /><br />
etc. other situations in the kind of “gray area” like above.
One does the above to “scratch an itch” that has become too much, otherwise one may commit something more serious, such as rape.
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If this is the case, then the “benefit” is a bit of a thrill, which is fleeting, but the downside is too grave, and I can think of just a few:
(1) It’s easily addicting, as Christian pointed out. This itch does not go away with the above activities; instead it comes back stronger, and it may lead one into “grayer” areas with time.
(2) As Nibbid83 said, there are derivative circumstances concerning the person accepting money for sex we are not aware of. What if we are aiding to perpetuate such an “industry”, further harming people in it.
(3) Harm to ourselves — the most serious one, leading ourselves away from nibbana. Not only that, according Sir Lal, this may be apayagami kamma.
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So, how does we cope with it? As a puthujjana, I don’t know, but I have found this very helpful, and I can vouch that nirāmisa sukha is real:
Three Kinds of Happiness – What is Nirāmisa Sukha?
There are 3 kinds of happiness, and sex is an example of sāmisa sukha, which is too short-lived. Convince the mind of a more stable happiness — nirāmisa sukha — and it will wean itself off sāmisa sukha.
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Best of luck to anyone going through this! This is a tough one. Anyone with ideas — especially anagamis — please chime in.<br /><br />
Lang