There are several indications in the birthchart to see & understand an individual’s sexual style.

1) Mars : Drive & action
2) Lilith :
Fantasies & darkside
3) Eros :

Mars in the signs

Aries : Dominant – Daddy-Mommy – Primal // Quick 
Taurus : Daddy-Mommy – Owner – Foodsex – Ropeplay // Sensual
Gemini : Dirty talk – Ploy – Gay – Swinger – Sexting // Playful
Cancer : Submissive – Little – Tits – Oral // Nurturing
Leo : Performer – Mister-Mistress – Sextape – Sugar // Fiery
Virgo : Mentor – Slave – Pet – Anal // Serving
Libra : Romantic – Bottom – Submissive // Gentle
Scorpio : Switch – Powerplay – Dominant – SadoMasochist // Soulful
Sagittarius : Exhibitionist – Nudist – Voyeur // Adventurous
Capricorn : Master-Mistress – Powerplay – Sadist // Longlasting
Aquarius : Roleplay – Chatsex – Freak // Perverted
Pisces : Brat – Experimentalist – Submissive – Feetfetish // Romantic

Lilith in the signs

Aries :
Very dominant by impulse. Fiercely competitive and independent. Can be ruthlessly aggressive. Wants it now or not at all. Must learn to control their extreme passions.

Taurus :
Irresistable, incredibly sensual. They love sex and affection and will do almost everything for pleasure. Must learn to control their sensuality and possessiveness.

Gemini :
They are never satisfied. Very curious, superficial and skeptical. A bit childish. They have extreme moodswings. They must learn to communicate about what they want.

Cancer :
Very submissive and highly intuitive. They can become emotionally manipulative. Suffer with intense separation anxiety. They must learn to find independence.

Leo : 
Narcissism, attention seeking and mirrors turn them on (so they can watch themselves perform). Sex is performing to them. Must learn to tame the ego.

Virgo : 
Obsessive perfectionist. Sexual servant, enjoys degrading sex. Suffers from  sexual shame and repression. Must learn to overcome feelings of guilt.

Libra : 
Incredibly seductive. Irresistable charm. Must learn to accept people as they are.

Scorpio : 
Incredibly seductive, hunting down lovers like prey. Hauntingly erotic sex. Obsessive and jealous. Must learn the value of trust.

Sagittarius : 
Wants everything in excess. Easily aroused. Must learn to have faith.

Capricorn : 
Completely ruthless. Become bitter and ice cold when hopes and desires are not met. Career is often connected to sex. Must learn to draw a line between emotions and ambitions.

Aquarius : 
Sexual rebel. Outspoken and obsessed with freedom. Must learn empathy.

Pisces : 
Fantasy over reality. Submissive, voyeurism. Sex is their escape. Deeply repressed emotions. Must learn to draw a line between reality and fantasy.

More info on Lilith :

Eros in the signs

Aries : Intensely passionate, spontaneous attractions, need for excitement
Taurus : Monogamous, Primal affection, scent, tendency to possess
Gemini : Foreplay, dirty talk, mental stimulation
Cancer : Sex is nurturing, intuitive, caring and tender
Leo : Loves to be worshiped, affairs, passion, drama
Virgo : Sober, need for mutual intellect and approach to sex
Libra : Romantic, submissive, very focused onto the partner
Scorpio : Mystery, sexual merging, transformative experience, primal
Sagittarius : Sex is sport, optimistic approach, adventurous
Capricorn : Needs cooperation & hardworking partners are seen as sexy
Aquarius : Need for odd things, mental approach, pure and raw
Pisces : Sex is a spiritual act, desire to be needed, self-sacrifice

Sexual Behavior 

The Descendant in the natal chart gives more information on what an individual wants and needs within sex,
how they act.

Fire DSC : Enjoys performing, involved in sexual activities. Takes a long time to climax
Earth DSC : Practical and sober
Air DSC : Secret liking for sex. Trying to conceal their sexual feelings.
Water DSC : Highly passionate, Not very sex oriented.

• Movable/ Dual Signs : Native likes to separate immediately after sex
• Fixed signs : Native likes to remain in deep embrace after sex

Natal Placements 

Mars conjunct or trine Uranus : Kinky
Mars conjunct Venus : Sexy and magnetic
Mars conjunct Northnode : Nymphomaniac
Mars conjunct Pluto : Powerful, dominant and very passionate
Mars square Venus : Dominant, not a very feministic sexual style
Mars opposite Uranus : Unconventional desires, kinky
Venus conjunct Northnnode : Never really satisfied
Sun conjunct Pluto : Dominant
Sun conjunct Northnode : Strong masculine energy
Lilith conjunct Uranus : Unconventional desires

Planets in the 7th house : 

• Sun : Aggressive in sex
• Moon : Excitement and readiness for sex
• Mercury : Premature ejaculation or nervous exhaustion
• Venus : Love for sex, Very aroused
• Mars : Vigorious and impatient
• Jupiter : Engagement in ardent love
• Saturn : Cool sex and mean outlook on sex union
• Uranus : Independent and unconventional in sex
• Neptune : Sex addicted
• Pluto : Obsessive desires and very dominant
• Northnode : Unsatisfied, sex for exchange
• Southnode : Hypersensitive, premature discharge