All of the planets in astrology have some sexual significance, but four in particular are of primary importance. These four are; Earth, Venus, Mars, and Pluto, respective rulers of the "sex signs" Libra, Taurus, Aries, and Scorpio.

1)Earth(Ascendant)/ruler of Libra: is the outer package or initial captivating factor in any case of sexual or physical attraction, and the spiritual or soul component(Sun, Mars, Jupiter) is what is being attracted to it. Someone with the Sun, Mars, or Jupiter in Leo, for example, will be attracted to someone with the Ascendant in Leo or any other sign of the same or opposing element. One of the strongest attractions is Sun opposite the Ascendant. The exactness in degree will intensify the effect.

The Earth/Ascendant or Rising sign is at its most physically and personally attractive in Libra, followed by the other two air signs, and then the fire signs. The Ascendant is not generally attractive in the earth or water signs.

2)Venus/ruler of Taurus: goes beyond outer packaging or form to the more substantial elements of sexual attraction. If the Earth/Ascendant is the skin, Venus is the flesh. Any of the other planets closely contacting someones Venus will produce a certain measure of erotic attraction. Of particular import are an individual's Mars, Pluto, and the Ascendant in the same sign, element, or gender as the other's Venus. the Venus/Venus can also be attracting. The exactness by degree will intensify the effect.

Venus is at its most sensual and attractive in Taurus. These people can be physically stunning if other factors(like the ascendant) are also well placed. Venus in the other two earth signs is also attractive, followed by Venus in Scorpio and the other two water signs. Venus can be rather shallow in the air signs and too aggressive in the fire signs.

The Venus/Mars Relationship: This is supposedly the main indicator or barometer of sexual compatibility between two people. At least one compatible Mars/Venus contact(by sign or element) is required, although two ways would of course be ideal. Preferably, the man's Mars should be conjunct, oppose, trine, or sextile by sign (the exactness of degree intensifies it) to the woman's Venus, although it can work the other way around as well. Such contacts bring out true affection and while they may not be all that exciting at first, they grow with time and bring satisfaction, even among members of the same sex. Incompatible Venus/Mars contacts are often very exciting(especially the square and quincunx) and are the stuff of affairs, but they usually don't last long and often deteriorate to the point of grating or hurting one another. Venus will resist the advances of an incompatible Mars, and while this can incite Mars all the more, it usually brings much tension and sometimes even violence.

3)Mars/ruler of Aries: When Mars is well-placed(in fire or air) it keeps the body trim and gives a good supply of energy. Whereas Venus and the Ascendant play basically receptive sexual roles, Mars(and Pluto) are the aggressors. Mars makes the first move and is either welcomed or refused by Sun, Moon, Venus, Ascendant, or any other planet it comes into close contact with. Mars is your libido or sex drive and the sign or element its in will determine what challenges or turns you on and how you take charge sexually.

Mars is at its strongest in Aries and the other two fire signs, followed by Libra and the other two air signs. Fire Mars people seek to be challenged personally, physically, and directly, whereas Air Mars people seek to be challenged mentally and socially. Mars is weak and effeminate in the water signs and crude or bullyish in the earth signs. People with both Mars and the Ascendant in earth or water have sluggish constitutions and are often noted to be overweight.

4)Pluto/ruler of Scorpio: Just because Pluto is so far away does not mean it cannot have a personal influence. Far from it. Pluto can be every bit as personal as any other planet, especially when it comes to sex. The Earth/Ascendant is what makes sex visually and mentally attractive. Venus is what makes it good to the touch. Mars is the challenge and making it happen. Pluto is the emotional, intensity of it all. Without Pluto there would be no build up or orgasm. Pluto in close contact to Venus, Mars, or the Ascendant produces intense sexual relationships. Pluto conjunct Venus, natally or by transit, is particulaly potent.

Pluto is at its best in Scorpio and the two other water signs, followed by Taurus and the other two earth signs. Pluto's depth and intensity is misplaced in the air or fire signs.

People who have only these four planets well-placed in their charts are often extremely attractive and desirable both physically and sexually. Of primary importance is a well-placed Ascendant(in air or fire), followed by the other three; Venus(in earth or water), Mars(in fire or air), and Pluto (in water or earth). The remaining eight planets or factors -Sun, Moon, Mercury, Jupiter, Saturn, Uranus, Neptune, and Midheaven, well-placed, will add further to this attractiveness.

5.The Sun is the playful and creative aspect of sex. The Moon is the emotionally magnetic side of it. Uranus is the novelty, experimentation, and excitement. Neptune is the glamour, seduction. and imagination. Jupiter is the risk and adventure it all. Mercury is the talk and the mind games. Saturn is the expertise or technique. I'm not sure how the Midheaven fits into it.