Sort by
Relevancy

Free Stories

62%
Crossdressed Lana - Hannover, Germany
Crossdressed Lana - Hannover, Germany Very Sexy & Compliant Sub-Slut Is Searching For Kinky BDSM Live-Dates At Hannover, Germany!!! I Am Bisexual And Want Men, Woman, Couples And Trans For Outdoor, Swingerclub, Porncinema And Public Sex. I Love To Wear Very Hot & Sexy Clothes Like Lingerie, Stoc... Read full Story
Crossdressed Lana 2020-02-06 4,483 Stockings Crossdresser Group Sex Outdoor Bareback Fetish Blowjob gangbang Lingerie domination Latex Sex Toys double anal
100%
Fender Bender Chapter 9
My name is Robert, I have been cross dressing since I was 14. I turned 18 last summer and this story takes place during my senior year in High School. I am 5'9" 160 pounds, blonde hair and blue eyes. When I am dressed I call myself Vicki. __________ I had met Julie at a recent party. Well... Read full Story
shemale lover 2012-07-27 3,554 Group Sex Cumshot Sex Toys
100%
Ein etwas anderes Grillfest 31.07.24
Am 31.07. wollten wir eigentlich ein geiles Grillfest in der Ruine Anwil feiern. Leider machte Petrus kurzfristig nicht mit, so dass wir bei Andrea Obdach fanden. Nach und nach fanden alle Gäst:innen bei Andrea ein. Andrea begutachtete, als gute Gastgeber:in, die mitgebrachten Würste, während der G... Read full Story
Cheryl_F 2024-09-02 183 anal Group Sex Cumshot Bareback Creampie Blowjob Big Cock Ladyboy gangbang Guy Fucks Shemale Ass to Mouth shemale fucks shemale cum in mouth
100%
Becoming Marie Chapter 4
During the following week I had gotten hornier and hornier thinking of the wekend visit to the air raid shelter. I popped into town during the week to get some make up and some clothes to wear for the following Sunday. This was going to be a bit awkward, but egged on by my urges i set off shopping. ... Read full Story
shemale lover 2012-03-23 3,479 anal Group Sex oral Sex Toys
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 5,103 Group Sex Cumshot Bareback Shemale Fucks Guy Blowjob Big Cock gangbang domination Sex Toys Mature cum in mouth shemale + shemale
100%
Force Feminized up Asshole
"Yea I thought the singing was OK but I don't really go for that style too much" "And the girls?" Brian prompted me. "Oh come on Brian leave him alone we all know he's not really interested in girls." "Give him a chance, people can change! Perhaps Carl's d... Read full Story
shemale lover 2012-02-13 6,787 anal Group Sex Fetish cum feminisation
20%
A surprise for John
It was a busy day at work when I got a text message from John asking what I was doing that night. I replied that I had no plans. He told me he was leaving work early, if I wanted to stop by for a lil bit I was more than welcome. I told him I would. I did want to talk to him about a small trip I was ... Read full Story
shemale lover 2012-02-12 3,111 anal Group Sex cum
100%
Susan's First Time Part 3: Susan's First Party
The chauffer passed through a gate in the high brick fence just as the sun started to slide behind the distant snow capped mountains. The cobblestone driveway that wandered toward the main house must have been a mile or more long. Susan admired the immaculately landscaped grounds as they drove throu... Read full Story
shemale lover 2011-10-13 2,698 anal Group Sex Creampie oral
91%
Lake Surprise
After finals of my first year in college in a northern university, I was ready for some real relaxation back home in the warm south. During finals I had started thinking how nice it would be to borrow my brothers boat and hit the lake for a week. I talked my roommate into making the trip home ... Read full Story
shemale lover 2011-12-08 10,859 anal Group Sex Creampie
100%
The Boy is A Girl Now
When I turned 16, I decided to go to a gay bar to see what the deal was. I had not been with anyone ever but I was curious and very much feminine. I stole my older brothers ID and caught the Bus to go to the Ballgame, so I told my mom. Then I wound up at the gay bar just as they opened that night at... Read full Story
shemale lover 2012-05-09 3,837 anal Group Sex sucking rimjob
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 14,377 first time Teen (18+) Amateur Group Sex Big Tits Cumshot Outdoor Bareback Blowjob Big Cock Asian lesbian public place
100%
HOW ONE PEEPING TOM MORNING TURNED ME INTO A SHEMALE SISSY BITCH
It was while cutting across his back trailer park lawn around 7pm on misty July Saturday evening, when I first discovered that Mr. Parker was really a fag. How else could you describe a man wearing a long blonde wig on his head while below he wore only a large somehow stuffed pink lacey woman's bra ... Read full Story
CDDIXIE4U 2019-01-08 14,247 Teen (18+) Crossdresser Amateur Cumshot Masturbation Blowjob Big Cock Ladyboy Lingerie domination Guy Fucks Shemale Homemade Compilation Vintage cum in mouth
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 5,347 shemale gangbang facial
50%
Dirty Tranny gang bang
Deep breath Charlotte, step into the night air and strut your stuff girl. This is what I was born to do; I snuggle into my short white fleecy coat as my 5” platform heels click on the pavement. Glancing down I can see my shapely stocking clad legs and, the all important, ankle bracelet glit... Read full Story
shemale lover 2011-12-27 4,867 anal shemales Group Sex
66%
More from my closet....
......being single is so better to play my games, no wives to take up my day, no one to lie to anymore about where I went... I had a layover for 3days in Vancouver last fall, three days all to myself, with the aid of google maps I found the local steambath for men. Steamworks it was called, set... Read full Story
badbadboi667 2020-12-03 3,430 Amateur Group Sex Outdoor Bareback Fetish gangbang domination Ass to Mouth amature
100%
Marathon im Cruisingworld Kirchberg
Ich wurde um 11 Uhr bei mir zuhause von meiner Begleitung abgeholt, gemeinsam fuhren wir ins Cruisingworld nach Kirchberg. Angekommen, wurden wir sogleich nett begrüsst, danach ging es in die Garderobe und gleich ins Spiegelzimmer. Wir starteten den Tag zärtlich mit Küssen und Streicheln. Ich wurd... Read full Story
Cheryl_F 2024-09-02 181 anal Amateur Group Sex Cumshot Bareback Creampie Blowjob Big Cock Ladyboy gangbang domination Guy Fucks Shemale cum in mouth
100%
Being taught a lesson .......... I think!
How did I end up on my back in my own bed, legs straight up with my ankles over her shoulders, ready to have my ass fucked from a lost bet? A bet that Alma clearly cheated at as we discover. I was off to Thailand for a 16 week course in Thai massage at a school recommended highly by a friend I ha... Read full Story
Curious_billy 2023-11-12 8,631 anal Amateur Group Sex Bareback Creampie Shemale Fucks Guy threesome Big Cock domination Homemade Vintage cum in mouth
100%
Driving Miss Michele
Michele drove carefully through the cold wet dark streets. She was not used to using the accelerator and brake pedals of her compact sedan in high heels and she was debating whether to pull over and unbuckle the strap of the high heel on her right foot and kick it off. She didn't want to bring atten... Read full Story
shemale lover 2012-11-30 6,739 Group Sex sucking Sex Toys
100%
The Day I Went SheCock Crazy
I summed up courage to meet up with my old shemale flame Fransicca (she is a Malaysian but living in indonesia) ... messaged her, she sounded excited and asked if i minded her friend joining us. 'Why not' i said. It was settled. we booked a villa for the next day. I checked in early. cleaned up ... Read full Story
Sara Banks 2021-04-26 6,804 Group Sex Cumshot Outdoor Bareback Shemale Fucks Guy Fetish Blowjob blonde Big Cock Asian Ladyboy gangbang
50%
Feriengruss 18.07.24
Um ähnliches, wie im folgenden Bericht, mit mir zu erleben, ist es notwendig, dass man sich sehr gut kennt. Alle Handlungen sind miteinander abgesprochen und es ist beidseitig ein tiefes Vertrauen vorhanden. Nicht nur, dass mir nichts passiert, auch dass ich meine Grenzen während des Spiels klar kom... Read full Story
Cheryl_F 2024-09-03 168 anal Small Tits Amateur Cumshot Bareback Creampie Fetish blonde Big Cock Ladyboy Shemale and Girl Sex Toys small cock
80%
Transsexual Savage
John had walked for eleven days. He was headed towards Fort Winston at the Hiat River, and he still had about three days ahead of him. The Hiat River was the natural border that separated the civilized world, where he came from, and the savage and brutal wilderness, where the natives lived and pract... Read full Story
Anal Orgasm 2020-07-10 6,452 Big Tits Outdoor Masturbation Bareback Creampie Shemale Fucks Guy Blowjob Guy Fucks Shemale
100%
badbadboi's walk in the park
...My boi hole was freshly washed, shaved and lubed with a lovely hot shower, my wand is perfect for cleaning my pussy, flushing it clean very time, I luv to let the water spray my hole driving deep enough to tickle the bottom of my prostate. My cock cage locked in place, my white crotchless panties... Read full Story
badbadboi667 2021-04-06 3,881 Crossdresser Amateur Group Sex Outdoor Bareback Creampie Blowjob Interracial Homemade Ass to Mouth cum in mouth
88%
First Time Outdoor Festival Fantasy
Fantasy Setting: Summer time in the mountains of Colorado the perfect bluebird weekend we all dream of. The day before an underground rave in the mountains all my friends bail on the show and was now left with either not going or going solo. Well I deiced what the hell and I'll go solo an... Read full Story
xaviergc8 2016-10-26 9,762 anal first time shemale gangbang bondage outdoors fuck toy
50%
Freak House Superstar Come Fest
Kiki and Ty Blaze were doing their thing. They were living on their love and passion, literally. The couple had taken their love, passion and desire to please one another and turned it into their livelihood. They had become stars in the world of underground porn. Their production studio, Nasty Nigga... Read full Story
shemale lover 2012-02-01 6,503 anal shemales Group Sex
50%
Two cocks and a pussy
I'm alone in my apartment and super horny, so I decide to have some kinky alone fun time. I strip and shave my body. I'm smooth now. I put on a sexy thong and bra. Next I put on a garter belt and super sexy thigh highs. Next I put on a super short and sexy skirt, lastly I put on a lace blouse. Next ... Read full Story
spreadforalldik 2024-07-09 2,798 anal Crossdresser Group Sex Cumshot Bareback Fetish Blowjob cum Lingerie pantyhose crossdressing Ass to Mouth cum in mouth
100%
The best of two Worlds Part 4
After our adventure on the beach Jacqui had a moral and physical hangover for a few days. She would do things to me that went beyond my expectation. She was absolutely fascinated with my cock, giving me head jobs the moment I walked in to the door. Upon my arrival home I would find her half naked, h... Read full Story
shemale lover 2012-04-26 2,723 anal sex Group Sex Blowjob orgasm
100%
Florida TG Experience
I had known Jan from High School, we always had an attraction for each other but were dating someone else or married at the time. Jan had actually married a friend of mine and I was envious of course. She at that time had sandy blonde hair, and a body to die for. One evening we had them over for dr... Read full Story
Jon Paul 2018-08-13 11,291 Group Sex Big Tits Bareback Creampie Blowjob blonde Asian Ladyboy Shemale and Girl Guy Fucks Shemale Ass to Mouth cum in mouth double anal
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 7,501 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
89%
Cast party
My name is Dan, and I have always considered myself an adventurous and open minded person, but my experience was taken to a whole new level in my junior year of college when I got involved in an amateur theatre group. We all got along astoundingly well and I found myself becoming friends with severa... Read full Story
shemale lover 2015-06-13 15,224 shemales gay male Group Sex
100%
Working for a Living Chapter 6
I slid out of the old Ford truck driver's side door. Surprisingly, my legs felt a bit shaky as my feet hit the concrete driveway of the Malibu mansion. I nervously straightened my cut-off shorts as I walked around the truck. She was waiting by the tailgate with a big smile on her face. "Wow Jai... Read full Story
shemale lover 2012-10-05 3,757 Group Sex Creampie threesome
100%
Reshooting the Scene, Chapter 1
I have been a porn aficionado since I was a teenager. My first dabblings were with Hustler magazine and a *very* hardcore mini-novel called “Her Busted Asshole,” which told the raunchy story of Ginny Cummings’ sexual coming of age. In addition to the very graphic story, it had full color glossy p... Read full Story
Lovelace 2021-06-07 4,784 Bareback threesome Blowjob blonde Big Cock Sex Toys Ass to Mouth
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 4,610 Group Sex Big Tits Cumshot Bareback Fetish Blowjob Big Cock Asian Ladyboy Sex Toys Mature cum in mouth shemale + shemale
100%
Surprise Ending (Part Three)
I rolled my dick around her hole to spread the precum off it and lubricate it. The feeling was sensational and I couldn't spend much time easing my way in --I shoved right in the the hilt in one steady push. Karla practically jumped off the couch and screamed. I thought maybe I had hurt her (I am... Read full Story
Chantel13 2022-08-23 4,521 Crossdresser Amateur Group Sex Cumshot Outdoor Creampie Shemale Fucks Guy Big Cock Shemale and Girl redhead Guy Fucks Shemale Ass to Mouth
100%
A Series of Perverse Dreams, Part 1
My relationship with Hannah had always been mutual in the idea that neither one of us was ever truly the dominant one. It was an equal, balanced relationship of mutual fucking and sucking. However, I had REALLY enjoyed being made into a submissive sissy slut by Nikki. Something changed in me after o... Read full Story
KaceyKlarissa 2024-02-24 5,844 anal Small Tits Crossdresser Group Sex Big Tits Outdoor Big Cock gangbang domination sissy femboy Ass to Mouth cum in mouth
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 3,538 Crossdresser Group Sex Big Tits Cumshot Blowjob blonde Big Cock Ebony gangbang domination pantyhose
50%
Trannies Feminise My Bum
"Yea I thought the singing was OK but I don't really go for that style too much" "And the girls?" Brian prompted me. "Oh come on Brian leave him alone we all know he's not really interested in girls." "Give him a chance, people can change. Perhaps Carl's developing... Read full Story
shemale lover 2012-02-01 4,481 shemales gay male Group Sex
100%
Trannies Feminize Dandy Boy
"Yea I thought the singing was OK but I don't really go for that style too much" "And the girls?" Brian prompted me. "Oh come on Brian leave him alone we all know he's not really interested in girls." "Give him a chance, people can change! Perhaps Carl's... Read full Story
shemale lover 2012-05-01 4,447 Group Sex Fetish ass fucking oral sex feminization
94%
CD and BBC Gangbang 1
My name is Mike, as a "Gurl" I go by Fiona. I am a gay man, mid thrities, white, 5' 9' 165, reasonably handsome, both in and out of women's clothes. One of the ways I express my sexuality is to dress as a woman and get fucked by other men. Preferably in a humiliati... Read full Story
FionaFucked 2014-10-27 14,169 Group Sex gangbang Interracial cd sissy
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 4,190 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
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 6,285 Teen (18+) Crossdresser Group Sex Big Tits Bareback Creampie Big Cock gangbang domination Guy Fucks Shemale Interracial double anal webcams
100%
the orgiastic fever of a trans-milf
Simulating a woman, or the orgiastic fever of a trans-milf It's been two months since I moved to the megapolis, where I've discovered several places where the third gender goes. One of my first explorations was a huge lingerie shop in a MALL; I wanted to buy some sexy stuff without being noticed ... Read full Story
hippocampus_171 2024-09-04 1,778 anal Amateur Cumshot Creampie Shemale Fucks Guy Latex Sex Toys Mature small cock
75%
Dissidia Final Fantasy
Floating in an ocean of azure blue and ivory white clouds, a single castle main castle levitates in the epicenter of the area in front of the three travelers, while a smaller castle hovered adjacent to it. Traveling on a beam of concentrated magic that connected their previous world with this one, t... Read full Story
BoyVixen 2016-03-28 5,547 pussy oral sex dickgirl
100%
A Schoolgirl Story Chapter 2
I must apologise for the amount of time that it has taken for the second chapter of this story to come out. I have to admit that I had kind of abandoned it, but all your lovely feedback comments made me decide that I couldn't leave this one hanging. So thank you to everyone who wanted more of Wendy,... Read full Story
shemale lover 2012-06-05 8,705 Group Sex Cumshot oral sex assfucking
100%
A Visit To The Booths
I walk nervously into the booths area. My heels clacking on the floor, as I enter the darkness. I pull my dress down, as its already riding up my ass. There are a few men waiting in the first hallway, checking me out as I walk past. I smile and head into the bigger area around the corner. There are ... Read full Story
shemale lover 2012-07-20 3,867 anal sex Group Sex crossdressing facefucking slut
65%
Marcia Goes Back to School
Marcia was painfully nervous. She hadn't been able to eat very much in days. The upside was she was even skinnier which would make Mistress and her husband very happy. She'd always been thin and on the diet Mistress Carol had her on she was already thinner than she dreamed possible. Her anxious stom... Read full Story
shemale lover 2012-12-19 10,796 Masturbation Blowjob blonde ass fucking big boobs
87%
THE ATTIC NOVEMBER 7
THE ATTIC NOVEMBER 7 – PART 1 THE JOURNEY AND GETTING READY. Susan had not had the opportunity to make the journey to the Attic dolled up to the nines so she made do with just wearing her black and pink lingerie under the hideous drab stuff (yuck). Having arrived early and parked up, she relaxed ... Read full Story
sexysusang 2018-03-09 6,096 Amateur Group Sex Bareback Blowjob Guy Fucks Shemale cum in mouth
84%
First Time: How I Love Cock
The first time I ever sucked a dick was when I was around 12 years old. I was at a sleep over with a friend. We were camped out in his backyard in a tent and he started things out tentatively by asking about my luck with the ladies, which was non-existent. Then he suggested that since neither of us ... Read full Story
wickeddogg 2019-12-11 34,014 Teen (18+) Cumshot Bareback Blowjob cum in mouth
100%
College project surprise
So this story happened while I was still in college and remains without doubt, the craziest, most exciting experience of my life. So I the story begins one day when I walking to class. I went to a big university so my walk was quite long, and the first 1/3 was just through off our campus housin... Read full Story
Jsmithsub 2020-09-16 21,465 Group Sex Bareback Shemale Fucks Guy Fetish threesome Big Cock Ebony domination Ass to Mouth cum in mouth
83%
Did I Do Right By Taking Money For Sex?
I first properly dressed when 14. (I did do the knickers and stockings and pantyhose thing previously from when I was 11). I first had sexual contact with a friend when we were both 14, i.e. wanked each other then I sucked him off and drank all his cum. I then waited until I was 16 for sex with... Read full Story
Linda Tiffany Vista 2024-05-07 3,219 anal Blowjob blonde Lingerie shemale fucks shemale cum in mouth teen (18+)
100%
My Noisy Upstairs Neighbors Part 3: Making Porn
In Part 2, I recounted how Paul, my commanding upstairs neighbor, coerced me into making porn with him and his younger roommate. Now, I'm excited to share the first video we created together. At 12:45 PM on Saturday, I nervously approached Paul's door. After knocking, Paul opened it with a smile ... Read full Story
Chrissy Tunnell 2024-07-16 3,175 Crossdresser Amateur Group Sex Bareback Fetish Blowjob Ladyboy gangbang Lingerie domination Guy Fucks Shemale sissy femboy
100%
Secrets
Jon had invited me to spend another weekend at his place with another of his friends. I always find his friends to be interesting so I accepted. Jon had given me a garage door opener and a key to his home after my first visit. He met me as I parked my car in the garage. He was wearing his usual skim... Read full Story
shemale lover 2011-11-01 6,303 anal Blowjob transvestite
100%
The Invitation
"You see, we have to come up with something that would be so embarrassing for you that there is no way that you would ever show those pictures of me to anyone, regardless of how d***k you got, or how horny you got or how pissed off at me you were,” Sally went on. “Something that wou... Read full Story
shemale lover 2012-03-20 6,304 Group Sex crossdressing feminization
100%
Fender Bender Chapter 4
My name is Robert, but when I am dressed I call myself Vicki. I am 5'9" 160 pounds, blonde hair and blue eyes. I had just turned 18. It was Tuesday evening and I had stayed home alone all day. I had a lot to think about. I was relaxing and listening to some music on the stereo. Mom had just ... Read full Story
shemale lover 2012-07-26 3,302 anal Creampie oral sissy
100%
Fender Bender Chapter 7
The main Characters are as followed: My name is Robert, but when I am dressed I call myself Vicki. I am 5'9" 160 pounds, blonde hair and blue eyes. I turned 18 a few months ago. Gary is almost 6', 185 pounds. He has short blonde hair and dark blue eyes. He has a nice tasty 7 1/2 inch cock... Read full Story
shemale lover 2012-07-27 3,263 Creampie ass fucking domination oral sex sissy
88%
Alex and Jon
Alex was not beautiful, but had a sexy attractiveness that most could not help but take a second look. This was the case with Jon as he searched adult Friend-Finder ads for someone that would satisfy his desires and dreams of a companion. Alex, a transgendered Filipina girl, had the bronze skin colo... Read full Story
Jon Paul 2022-09-21 5,537 Group Sex Cumshot Bareback Creampie Shemale Fucks Guy Blowjob Asian Ladyboy Guy Fucks Shemale cum in mouth
95%
Once a Slut Always a Slut
I held my breath – and then I knew I had crossed a line – I had become by my submission, in that instant of time, another individual. I had known Paul Phillips since I had arrived at the local school in the village some 6 years before. We had moved on together to the grammar school in... Read full Story
shemale lover 2015-06-17 12,130 first time shemales Group Sex