Men love sex because sex is to conquer; to subdue and to win the desires of a woman by pleasing her and finally pleasing himself. The outcome (no punn intended) is to find the best suited woman to have and raise his children.

~ OK. That was the prehistoric instict expression.

Men love sex because if they dont' love sex, they will end up alone, lose custody of their children, lose their home, half their income and anything they can't carry away in one trip.

~ OK. That was the 21st century cynical expression.

Men love sex because sex feels fantastic.

From the words of Wikipedia:

In men

During orgasm, a human male experiences rapid, rhythmic contractions of the anal sphincter, the prostate, and the muscles of the penis. The sperm are transmitted up the vas deferens from the testicles, into the prostate gland as well as through the seminal vesicles to produce what is known as semen. The prostate produces a secretion that forms one of the components of ejaculate. Contraction of the sphincter and prostate force stored semen to be expelled through the penis's urethral opening. The process takes from three to ten seconds, and produces a warm and highly pleasurable feeling.

Normally, as a man ages, the amount of semen he ejaculates diminishes, and so does the duration of orgasms. This does not normally affect the intensity of pleasure, but merely shortens the duration.

After ejaculation, a refractory period usually occurs, during which a man cannot achieve another orgasm. This can last anywhere from less than a minute to several hours, depending on age and other individual factors.

Sensation

As a man nears orgasm during stimulation of the penis, he feels an intense and highly pleasurable pulsating sensation of neuromuscular euphoria. These pulses begin with a throb of the anal sphincter and travel to the tip of the penis. They eventually increase in speed and intensity as the orgasm approaches, until a final "plateau" of pleasure sustained for several seconds, the orgasm.

During orgasm, semen is usually ejaculated and may continue to be ejaculated for a few seconds after the euphoric sensation gradually tapers off. It is believed that the exact feeling of "orgasm" varies from one man to another, but most men agree that it is highly pleasurable.

In women

A typical woman's orgasm lasts much longer than that of a man. It is preceded by erection of the clitoris and moistening of the opening of the vagina. Some women exhibit a sex flush, a reddening of the skin over much of the body due to increased blood flow to the skin. As a woman nears orgasm, the clitoral glans moves inward under the clitoral hood, and the labia minora (inner lips) become darker. As orgasm becomes imminent, the outer third of the vagina tightens and narrows, while overall the vagina lengthens and dilates and also becomes congested from engorged soft tissue.

Orgasm and the brain

For women: During stroking of the clitoris, the parts of the female brain responsible for processing fear, anxiety and behavioral control start to relax and reduce in activity. This reaches a peak at orgasm when the female brain’s emotion centers are effectively closed down to produce an almost trance-like state.

52% of women fake orgasm:

For a variety of reasons, some people choose to fake an orgasm. A recent Redbook survey shows that 52% of women regularly fake orgasms. Only 17% are likely to have an orgasm during sexual intercourse, because the clitoris often is not stimulated enough by intercourse alone. 43% of women report “some kind of sexual problem,” such as inability to achieve orgasm, boredom with sex, or total lack of interest in sex.

Women do not necessarily need to acheive orgasm to feel sexually satisfied. Men, on the other hand, need to acheive orgasm to feel sexually satisfied, in most cases.

Why else? It is not only a 'release' for men, but it feels good as well. For women, if you have found the right 'match and fit for yourself, not so much as a 'release' but it feels good as well. Females are more emotional based where men are more on the physical aspects when it comes to LOVE.

I think sex is not outrightly equally as a result of love but of lust. Men love sex because that is how their body chemistry is but women love sex too when men handle it properly

Sex is equally a result of love... so i love sex!!!!!!!!!

It feels really good. And despite all the stereotypes, I think they want love and affection, too.

everybody likes sex if it's done the right way, because sometimes lets face it some guys are lost and a mess, but i agree with Lyz Lenz :)

Same reason women love sex. It's fun!