Sort by
Relevancy

Free Stories

56%
Big cock shemale from Pune, India
I just saw her profile on Planet Romeo, her name is ID is Kaynat / Muskan. I saw her photos and got attracted to her. I am always a big fan and lover of Shemales or TS. I called her and fixed appointment by negotiating with her for 2500 INR. I went to meet her, she stays in a condominium in ... Read full Story
Stud4Shemale 2017-05-22 96,239 Big Cock Asian Ladyboy Guy Fucks Shemale Ass to Mouth cum in mouth
100%
Big Dick Alessia Visits Dallas
Alessia Hung Mature MILF travels to visit a Big Dicked Man and his Sexy Household If you like Transexuals, big cocks, bondage, BBWs, big clits, deep throat, fisting, 69, ass fucking, sounding, piercing, cum swallowing and big loads this story is for you. If not don't bother reading. If you fav... Read full Story
darrell 2022-04-20 4,540 Group Sex Cumshot Shemale Fucks Guy Blowjob blonde Big Cock Asian Shemale and Girl Sex Toys Mature Ass to Mouth shemale + shemale
87%
They Were Right
They were my friends, but I'd had sex with both of them. Not at the same time, but I had dated the one for a month and just started dating the other. So, although the thought had never crossed my mind before, I found myself dressed up as a girl for Halloween. After we had partied at a few clubs and ... Read full Story
shemale lover 2011-12-29 5,951 shemale Big Cock porn
100%
Hung Trans Lesbians Fuck Two Ladyboys
Note 1: If you like Transsexuals, Trans Lesbians, Asian Ladyboys, Big Cocks, Extreme Cock Sucking, Anal Fucking, Anal Fisting, Semen Swallowing, Role Play, Orgies, BDSM, Cock Sounding and Foot Fetish this story is for you. Note 2: All the characters are over 21. The names are fictitious, but some... Read full Story
darrell 2022-01-03 4,548 Group Sex Big Tits Cumshot Bareback Fetish Blowjob Big Cock Asian Ladyboy Sex Toys Mature cum in mouth shemale + shemale
100%
Groped on the Bus!
In real life I do not crossdress in public, I am not yet comfortable being my true transgirl self, I wear normal men's clothes and I look like a guy. So I look very different from my persona here. So...there I was standing among dozens of strangers at a bus stop. I kept looking up from my phone ... Read full Story
Chrissy Tunnell 2023-03-22 5,241 Small Tits Masturbation Fetish Big Cock Ladyboy Guy Fucks Shemale Frottage
100%
I was backstage giving blowjobs at a transsexual beauty pageant
I was backstage giving blowjobs at a transsexual beauty pageant I had this neighbor, who cross-dressers on weekends for a LGBT club. She invited me to an annual transsexual beauty pageant. Beautiful slutty shemales competing to be the official beauty queen for the club. She happens to be hosti... Read full Story
My Shemale Attraction 2024-08-07 2,887 Crossdresser Group Sex Big Tits Cumshot Blowjob blonde Big Cock Ebony gangbang domination pantyhose
100%
Horny Writing A Strange Habit
I enjoy watching videos which I can Vicariously live. This is nothing more than my horny hobby, an amalgamation of various thoughts. My form of hands free edging. Spell checked only, "No I haven't proof read a first draft, not trying to publish masterful works here." Hope to hear from those w... Read full Story
Araina 2021-03-08 2,848 Crossdresser Amateur Big Tits Cumshot Bareback Fetish Blowjob Big Cock Guy Fucks Shemale Frottage Homemade Ass to Mouth cum in mouth
50%
Gangbang: Daddy's Girl
"Oh yeah...that's daddy's girl," my dad moaned as he massaged my enormous round sticky ass. I'm 18 and my sister was about 5 years older than me, so who knew how long this had been going on for, I thought to myself. At least I tried to think as I slowly closed my eyes and bit my bottom ... Read full Story
shemale lover 2012-12-16 9,490 sucking cum gangbang
66%
A Series of Perverse Dreams, Part 3
After my last couple dreams, I began to watch a ton of gangbang and bukkake porn. I had jerked to this kinda stuff before but now I was watching it constantly and this time around, it was to the thought of being the girl in the scene. Something about watching a beautiful woman taking numerous cocks ... Read full Story
KaceyKlarissa 2024-03-08 4,871 anal Big Tits Cumshot Creampie Blowjob blonde gangbang big ass sissy Ass to Mouth cum in mouth bimbo bimbofication
42%
sexy jane story
I love the idea being a crossdresser wearing women outfit bars in panties n sexy outfit not just for the sex I love sex being on my knees sucking cocks in getting fuck by a big cock see win I was very young I had sex with 3 guys one day they ask me will I suck there cocks in I sand yes we want insid... Read full Story
45sexyjane 2019-05-27 4,345 Small Tits Crossdresser Amateur Big Tits Masturbation Blowjob blonde Big Cock gangbang Lingerie Sex Toys shemale + shemale sexy crossdresser
77%
Slut indiscretion
At 17, I had reputation among the people in my world. I had sucked more dicks than the average hooker. I had slept with men of every race creed and color. You can even throw in a mentally challenged lad or and autistic child as well. All because I loved getting sex. I think that a penis is the sexi... Read full Story
Regina10 2020-09-16 5,573 Crossdresser Big Tits Cumshot Bareback Blowjob Big Cock Ladyboy Lingerie domination Guy Fucks Shemale Ass to Mouth
75%
Passion in the Rough
Tonight, I was searching in vain for a parking place close to the club, but unfortunately, I had arrived late and there were no empty spaces close by. I drove around and went down several streets in the same block until I found an empty spot. That was perfect I thought as I found a parking place and... Read full Story
Regina10 2024-04-27 3,576 anal Crossdresser Big Tits Outdoor Bareback Creampie Blowjob blonde Big Cock Ladyboy gangbang Guy Fucks Shemale
100%
Alessia Travestita Hung Mature Blonde British Porn Star
Alessia Travestita Hung Mature Blonde British Porn Star If you like Transexuals, big cocks, bondage, domination, deep throat, fisting, spit roast, 69, ass fucking, cum swallowing and big loads this story is for you. If not don’t bother reading. If you like my story please leave comments and ... Read full Story
darrell 2022-01-03 4,965 Group Sex Cumshot Bareback Shemale Fucks Guy Blowjob Big Cock gangbang domination Sex Toys Mature cum in mouth shemale + shemale
100%
A Fairy Tale Part 2
=-=-Chapter Six-=-= I woke up sometime later and I was feeling better, even a little hungry actually, and I wanted a shower and I needed to pee and...I cocked my head as I heard the unmistakable sounds of Mistress Stacy's bed moving. She had a large one, king sized, with old springs or somethi... Read full Story
shemale lover 2011-12-06 6,857 Creampie Big Cock ass fucking
94%
Shemale Ride Along Part 1
I'm going go ahead and get this out of the way. During my freshman year of college, I was confused about my sexuality. It sounds strange saying this right after calling myself confused, but I loved girls. I really did. I loved all of their shapes and curves. I loved tits, pussy and ass. Now... Read full Story
qtball 2016-08-29 12,634 anal tranny Blowjob Big Cock bj asstomouth
86%
Cindy and Juanita Kinky Shemales
Her name was Cindy and she had been born a male. Cindy was a beautiful woman is every way except one. She didn't like the term tranny and preferred being referred to as a shemale. She was truly happy living as a woman. She began taking light doses of hormones at 19 she had stopped hormones beca... Read full Story
darrell 2016-11-30 11,278 anal Big Cock deep throat swallowing foot fetish piercing
91%
HOW MY AUNT AND SISSY NEPHEW CHANGED MY LIFE FOREVER! (fictional
It was the very first night of my month long North Carolina July summer vacation stay when my Aunt Meg suddenly entered the bedroom that I was temporarily sharing with my younger cousin Rudy. Being so openly effeminine in his body language,voice and looks, I had already planted such dirty thoughts ... Read full Story
CDDIXIE4U 2019-01-08 34,249 Teen (18+) Crossdresser Cumshot Masturbation Bareback Shemale Fucks Guy Fetish Blowjob Big Cock Ladyboy Lingerie domination Homemade Compilation cum in mouth shemale + shemale
100%
Sissy Slut Reunion
Rob had moved back to town and called me. He had just moved into his new place and he wanted me to come by and talk. I knew what he really wanted from the tone of his voice, because I wanted it too. He said he had been thinking and dreamed about me the whole time he was away. My spirits lifted and ... Read full Story
Regina10 2020-09-14 4,345 Crossdresser Big Tits Cumshot Bareback Creampie Fetish Big Cock Ebony Ladyboy Guy Fucks Shemale Ass to Mouth cum in mouth
90%
Sissy Slut and Stepdads
Frank was pumping me hard and his huge cock seemed to have grown and become extra hard. I am so thrilled that way he enjoys fucking my ass with such passion. I would almost think he was in love with me if this relationship wasn't so bizarrey. It’s ironic that as a male I always get total humiliation... Read full Story
Regina10 2020-11-30 9,435 Crossdresser Bareback Creampie Fetish Blowjob blonde Big Cock Ladyboy Lingerie Guy Fucks Shemale Ass to Mouth double anal
40%
Dating all whole my life
Julia and Ilya, together 10 years It was more than 10 years and 2 children ago. In December 2005, we agreed to meet at the gate of my office after a working day. I did not go out godlessly for a long time (40 minutes from the appointed time), but he still waited. I hope he does not regret it ... Read full Story
PornoDating 2019-08-15 4,144 Crossdresser Amateur Big Tits Cumshot Bareback Creampie Fetish Blowjob blonde Big Cock Asian gangbang domination Guy Fucks Shemale Interracial sex Mature Futanari Frottage Compilation Ass to Mouth Cartoon cum in mouth double anal dating life in Mars? life
75%
Fucking Insatiable
* Draenei futanari, as many of us have become intimately aware, are fucking insatiable. For many of the same reasons, they also have a tendency towards entitlement and ego issues. This is hardly surprising, being a magically-fueled blue-skinned space-babe with positively porn-star T&A and a d... Read full Story
shemale lover 2012-12-07 5,819 sucking gangbang Futanari
91%
Masturbation fantasies: Amanda, queen of the peep show
A guy visits a peep show with unexpected results. As he gets to watch a girl with something special, he discovers his hidden desires. This story contains: peep show – voyeur – gloryhole - fake tits – group masturbation – male masturbation – shemale – frottage - titfucking When William finall... Read full Story
ThatEroticWriter 2019-07-24 8,611 Big Tits Cumshot Masturbation Uniform Frottage
100%
A Perfect Pandemic: A Transsexual Transition in a Troubled Time
A Perfect Pandemic A Transsexual Transition in a Troubled Time A Novelette by Alexandra Rios Text Copyright Reserved © August, 2021 Dedication Transgender Day of Remembrance is a solemn occasion. I am offering “A Perfect Pandemic” for free as an antidote to the fear, phobia, discrimination, d... Read full Story
the greatest liar 2021-11-16 5,953 Teen (18+) Crossdresser Group Sex Big Tits Bareback Creampie Big Cock gangbang domination Guy Fucks Shemale Interracial double anal webcams
85%
BANGING AROUND BANGKOK
BANGING AROUND BANGKOK: THE AMOROUS ADVENTURES OF CAITLIN "MEOW" MORRISON after living and working in Thailand/SE Asia for many years i decided to write an erotic story based on some of the people i have known, venues and places i have been, and the P4P night-scene where i spent way too much... Read full Story
bkkldby 2019-06-17 14,302 first time Teen (18+) Amateur Group Sex Big Tits Cumshot Outdoor Bareback Blowjob Big Cock Asian lesbian public place
81%
A pervy uncle invited me to his house at 10 PM..!
It's been 8-10 years now, I had this amazing experience. I was standing at the bus stop in my area/street(my daily routine), one uncle was watching me but I ignored eye contact as I feel awkward the way he was looking at me because I act straight in public and I felt that he's seen my girly ... Read full Story
Cindy Sky 2021-07-20 7,374 Teen (18+) Small Tits Amateur Cumshot Outdoor Bareback Creampie Fetish Blowjob Asian Ladyboy Mature
62%
My Brother and I.
HI, I am Farzana,(have set my name recently,before that my name was Raja). I am Bangladeshi. I have been leaving with my family.Now I live with my Dad only.Some times, He invite his friends also. I will tell You about this later. I am 27 years old.The story I am sharing with You is about ...14 year... Read full Story
Esrat 2019-11-26 9,669 Crossdresser Group Sex Cumshot Creampie Fetish Blowjob Big Cock Asian gangbang domination Homemade cum in mouth
100%
Two CD's the first time we meet.....
We are meeting for the first time since talking online. I want to dress for you gurl, I want to feel as you do, I want to be your slut, your slave of desire. My panties are a sheer white, my hard cock can be seen ever so pressing against them, I rub myself for you as you watch, drooling now. Hand... Read full Story
kelliecdgirl 2024-04-10 4,120 Stockings Crossdresser Cumshot Masturbation Fetish blonde Big Cock Lingerie pantyhose Frottage sissy femboy shemale + shemale
100%
Gemini Sluts and Gang
My good friend Renee and I had set up a double date gang bang for tonight now that she was finally out of the closet and ready. She has decided that life is too short to remain in the closet and miss out on all the fun. Renee and I have so much in common. Besides loving sex, we both have a fetish f... Read full Story
Regina10 2021-04-09 4,601 Group Sex Big Tits Cumshot Bareback Fetish Blowjob blonde gangbang Lingerie Guy Fucks Shemale Ass to Mouth cum in mouth
100%
Nikki's Massive Strap-on
A quick recap in case you haven't read my previous stories. My name is Kacey. I'm 20 years old, white, 5'10" and 150 lbs. I have straight, shoulder length dark brown hair, light brown eyes and a thick, 6" cut cock. My girlfriend is Hannah, who also 20 years old and stands 5'10" weighing in at 140 lb... Read full Story
KaceyKlarissa 2024-02-23 5,059 anal Crossdresser Big Tits Cumshot Fetish Big Cock Lingerie Shemale and Girl domination big ass Futanari sissy cum in mouth
50%
Transvestite father异装癖的父亲和儿子被农民工虐待
'migrant worker S, good at foul language and humiliation, SP, heavy hands, is it acceptable?' On the SM dating software, a message popped up. Migrant worker S. What the hell? I casually click on his information, 39Get 186 and 76, dynamic is full of handsome muscles, muddy shoes, a glimpse of gar... Read full Story
Oldslut Sissy 2024-08-21 1,240 Amateur Big Cock Asian Sex Toys Mature sissy chinese
100%
A Series of Perverse Dreams, Part 2
Three or four days had passed since my torrid alley way dream. Hannah had recently come over to share a few glasses of wine and a steamy fuck session in the shower. She had definitely embraced the ways of edging I had shown her because when she came in my mouth I could barely contain the massive amo... Read full Story
KaceyKlarissa 2024-02-29 4,719 Crossdresser Big Tits Cumshot Bareback Fetish Blowjob blonde Big Cock big ass Futanari bukkake sissy cum in mouth
100%
Barbie Jo Adventures Part 5
Friday Night I've gone all week as Joe; no one at work has said anything to me about Monday morning. So I assume I got away without being exposed as a cross dresser. I was working late all week and finally Friday is here. I am so horny and anxious to become Barbie Jo. Hopefully someone will call,... Read full Story
shemale lover 2012-02-18 4,412 sucking Fetish cum swallowing
92%
MY Party Favor Fantasy
My Party Favor Fantasy A fictional story built around an old fantasy of mine I ran a notice on one of those sex sites that said” Help me fulfill my fantasy and I bet we take care of some of yours also. Hi there, I am Penny and I am a total bottom trans w... Read full Story
pennypenny 2019-01-08 7,440 Stockings Crossdresser Group Sex Cumshot Masturbation Bareback Creampie Fetish threesome Blowjob Big Cock gangbang Lingerie redhead domination Guy Fucks Shemale Sex Toys Ass to Mouth cum in mouth double anal
80%
Spankys mother cloths torn off on stage reveal she has cockoc
Erotic website remake of the little Rascals short film remake of Beginners Luck. The audience is laughing hysterically at Spanky attempts to open his stuck helmet. Spankys mother, a blonde beauty peeks out at the audience from the stage wing, as the crowd’s loud laughter, nervously biting her finge... Read full Story
kucksissylicktoman 2020-06-16 5,333 Big Tits Cumshot Masturbation Fetish Blowjob blonde Big Cock gangbang Lingerie Guy Fucks Shemale cum in mouth shemale + shemale
60%
The Clinic
I got out of my cab and looked up at the Clinic. It was a small, nondescript hospital. I was still pretty nervous about this treatment since I wasn't even sure of the details. But it was either this or go under the knife. This problem had to be dealt with. I picked up my bag and went into the lobby.... Read full Story
shemale lover 2012-05-02 6,030 Cumshot Big Cock jerking off oral sex cum swallowing
81%
Ladyboy Switch Story
I am messed up with how I feel about this. I still love looking at women. I love tits and arse. I like the soft feel of women – kissing them and feeling their bodies. I don’t look at men in public and get turned on – men with clothes on do nothing for me. Put me somewhere that I can see those same m... Read full Story
shemale lover 2015-02-27 7,182 Cumshot suck Shemale Fucks Guy Ladyboy ass fucking swallowing
100%
The Next Level
Nitromethane It's been a couple of weeks now since I sucked my last shemale cock and swallowed her load, and with enough distractions, it hasn't been too difficult keeping myself preoccupied and my mind off of satiating my new fixation. Still though, I do have my moments when I sit back and imagi... Read full Story
Gwapo67 2022-02-01 6,015 Bareback Creampie Shemale Fucks Guy Blowjob Big Cock gangbang domination cum in mouth
80%
My first foursome with shemales
I just want to say im a straight guy i love women but lately i have had dreams about fucking shemales, now im only 5'9 and have a 5 inch cock 6 inch fully erect. now i watch a lot of lesbian porn and im a little curious about shemales. now some girls i have fucked say im a great pussy lic... Read full Story
LordLucian 2014-01-20 5,649 Cumshot suck gangbang oral sex cum swallowing foursome
85%
My Awkward Phase
My Awkward Phase ©Alexandra Rios 2019 The greatest lie is that what happens in high school doesn't matter, because life begins in college. I pretended to agree, although I never believed it, for I was the world's greatest liar. Wannabees I was hanging out with my friends Quinn, Barb and Anne ... Read full Story
the greatest liar 2019-06-14 12,074 Small Tits anal sex Latina Masturbation Bareback Creampie Blowjob Big Cock transformation gangbang Shemale and Girl Guy Fucks Shemale Sex Toys Ass to Mouth cosplay hormones high school real life situations
84%
She never saw it coming
When I was 19/20 I used to frequent LGBT bars roughly twice every month. Most nights not much would happen but I found myself going to the trans nights more often. Until I eventually had some experience with trans girls. It was mostly fairly soft fun. Me getting oral and occasionally topping th... Read full Story
chris1989r 2022-02-01 5,290 shemale gangbang facial
60%
Susan's First Time Part 4
The shadows of late afternoon crept across the city when Susan paid the cabbie off. Why had 'he' wanted her to come down to this neighborhood? She looked around with apprehension at the garish lights of bars and adult bookstores flashing in the growing darkness. One or two streetlights flickered on ... Read full Story
shemale lover 2011-10-14 3,181 Small Tits shemale massage
100%
SheMale Pussy and Cock
I once had a friend who always said "never fuck anything you can't bench-press". He was right, the biggest benefit of having sex with someone smaller and lighter than you is you can lift them easily ! On a recent trip to Thailand I couldn't take my eye's off a stunning, short, tiny but ... Read full Story
shemale lover 2012-01-24 4,342 anal shemales gay male
100%
Blushing Bride Chapter 6
Chapter Six: Wedding Presents I was on an incredible high for a couple of days after my wedding. Like many bridegrooms on the day, I had felt very nervous, both about the day itself and the years of married life that stretched out before me. Only, I had a little more to be nervous about than many... Read full Story
shemale lover 2012-07-21 4,198 Cumshot Fetish oral sex
76%
Porn Princess
They say if you are going on a journey of revenge, to dig 2 graves, one for your enemy and one for yourself. I thought I understood the meaning of that saying, but never so much as right now. My name is Dan, and at the age of 21, I had been working for nearly 2 years as a production manager for ... Read full Story
shemale lover 2012-09-02 24,172 Cumshot Blowjob fuck fingering big boobs
100%
Exposure, Disclosure
The Greatest Liar, Exposure, Disclosure © Alexandra Rios 2019 Author’s Note: This is a continuation of the narrative which commenced with “My Awkward Phase”, which I posted here previously. Readers may wish to read that before continuing, although I have written them to stand alone. Natives s... Read full Story
the greatest liar 2019-06-18 7,815 Teen (18+) Small Tits Amateur Group Sex Latina Blowjob gangbang Guy Fucks Shemale cum in mouth
78%
Emily and Jane
I'm very proud and happy to publish another jewel today, a story about two shemales from 26-th century, Emily and Jane. Props for this truly delightful story to our forum member, Ila. Excellent work bro! It is the 26th century. Human genetics has advanced to the point where anyone born male or fe... Read full Story
shemale lover 2015-04-11 4,593 anal licking cock sucking
0%
A Long Friday Night
Labor Day weekend was coming up. It is the weekend that I let myself go. On this weekend I do something that I save for most of the year. I just do it for myself. This year I was going to try to get a date with a young lady called “Lee”. Let me tell you something’s about me first. ... Read full Story
shemale lover 2012-03-17 3,770 sucking Asian domination jacking off
90%
Big Daddy
BASED ON ACTUAL EVENTS As is the case with most hard drug users, you start off small and end up making your way up. Since I was 15 I had been smoking weed. One of my friends had introduced me to some other drugs like meth or coke a few years later. The weed was still a big influence but it all se... Read full Story
shemale lover 2012-06-09 6,151 Crossdresser Cumshot Fetish oral sex
87%
The Hotel Part 1
I knew when this started it would be like nothing I had ever done before. I drove up to the hotel early friday morning. I was checking in for seven days. Seven Days of non stop pounding of my asshole, Strapons, Crossdressing, fucked fem, huge dildos, and giant buttplugs are just a few of my fetishe... Read full Story
shemale lover 2012-02-11 6,186 Fetish cum domination Sex Toys
33%
A Certain Perception
Kyra was not the girl of my dreams. I never DARED dream a woman that good would just walk into my life. She was smart, sassy, vivacious, intuitive, resourceful, and a real 'people person'. We met in an Internet chat room called "Working Girls". We're not talking about the kind you find in ... Read full Story
shemale lover 2012-02-23 8,376 Fetish transformation dildo
100%
Shemale Fantasy - Suck Fest
This story is completely fictional - in fact it is a fantasy of mine that I will describe in great detail, contact details are at the bottom if you want to make this a reality! I arrive at your house on the evening. You let me in and show me to the spare bedroom. I walk in and close the door behi... Read full Story
shemale lover 2011-09-13 5,404 Cumshot jerking off pantyhose
40%
First Sexual Crossdress Experience
How my secretary found out I'm a bi TV and how me and my TV friend educate her into some of the more zany aspects of TV sex. *** As I laid back against the wall of the toilet with my nylon-clad thighs spread wide and my erect cock jutting up lewdly from between them, the wooden door in front o... Read full Story
shemale lover 2012-09-27 5,730 first time Fetish cum oral crossdressing nylon
100%
Which Are You?
Which are you? A, B or C? A) You treat me well. You insist that I look stunningly pretty 24/7. You insist I always wear make-up, care for my hair and nails. You pay for me to go to a beautician once a week. You buy me sexy lingerie. You get angry if I wear slacks or jeans. You prefer dresses in p... Read full Story
shemale lover 2012-11-22 3,088 Fetish Lingerie sissy
71%
A Night of Makeup, Cock and Cum - froam Annamalice
It was all I could do not to accept. After all, it's been a fantasy of mine for years. When given the opportunity, I had to go for it. I had been surfing the internet for crossdressers, shemales, transvestites and transsexuals. The idea of a hot woman with a cock had always turned me on. Further, I... Read full Story
shemale lover 2011-11-21 5,254 shemales Group Sex Fetish
100%
Blame Abba Chapter 3
Part 7 First date I do like making entrances, that was one of the best. I didn't wait for anybody's reaction, I just strode across the bar as easily as my tight skirt would allow. I didn't see Patrick at first, but Jeff was there, and he was looking at me. I had assumed none of my mates would be ... Read full Story
shemale lover 2012-07-18 3,589 first time Fetish oral sex crossdressing
100%
Bobbi from Tennessee
Six months ago ... "I'm leaving now, Bob," Sue called out as she left. "I'll be back in a couple hours." Bob waited until he heard the garage door close before going to their bedroom. He looked through Sue's underwear drawer before deciding on a sexy pair from Victoria Secr... Read full Story
shemale lover 2012-07-22 3,913 Cumshot Fetish oral sex