Sort by
Relevancy

Free Stories

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 4,328 Group Sex Big Tits Cumshot Bareback Fetish Blowjob Big Cock Asian Ladyboy Sex Toys Mature cum in mouth shemale + shemale
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 4,335 Group Sex Cumshot Shemale Fucks Guy Blowjob blonde Big Cock Asian Shemale and Girl Sex Toys Mature Ass to Mouth shemale + shemale
50%
A Married Marilyn
"Class is dismissed. Don't forget the project due…" "Huh, what?" Marilyn woke up disoriented from her nap. When she finally came to, she vaguely remembered some project for Intro to Computer Science, gathered her legs from the chairs in front of her, dusted off her b... Read full Story
shemale lover 2012-03-18 7,167 Group Sex Masturbation sucking Sex Toys
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 11,847 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
80%
fuck by my best friend's family
= Part 1. Alice's father = My name is Onikky 28-year-old Shemale from ASIAN, this story only shares the first experience of making love. The story begins when I first moved to a big city, looking for a new atmosphere, I don't have a place to live that I know is only my friend's name Alice who ... Read full Story
Onikky 2019-06-25 9,381 Amateur Masturbation Big Cock Asian Ladyboy gangbang Lingerie domination Guy Fucks Shemale Sex Toys Homemade Ass to Mouth cum in mouth
66%
Be My Bitch
After a long day at work, I get in my car, and look forward to the long drive home. It gives me time to unwind and relax. I try to forget about the hectic office and concentrate on my beautiful girlfriend waiting at home with that warm smile that she greets me with when I get there. However, tod... Read full Story
Go Balls Deep or Go Home 2018-08-06 31,342 Crossdresser Outdoor Bareback Blowjob Big Cock Ladyboy Lingerie domination Guy Fucks Shemale Interracial Sex Toys Ass to Mouth cum in mouth
92%
Nicole and I the final chapter
So I haven’t written any stories in a while , so if you read mine before you should like this one I didn’t write it yet cause it’s about my last encounter with Nicole. Very sad day for me lol but a very good story. So here goes........ Nicole and I had been going over a year now and everythi... Read full Story
Duke04 2018-03-07 4,294 Stockings Blowjob Big Cock redhead Sex Toys Ass to Mouth cum in mouth
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 5,137 Teen (18+) Crossdresser Group Sex Big Tits Bareback Creampie Big Cock gangbang domination Guy Fucks Shemale Interracial double anal webcams
100%
The Club
Pretty soon everyone was naked and in their places and ready to go. "Okay ladies, I'd like you to meet tonight's very special guest, may I present to you, Susi!!!" Missy swung open the door to the adjoining room, and much to the stunned delight of everyone there an incredibly beautiful Asi... Read full Story
shemale lover 2012-05-01 3,940 Group Sex shemale orgasm fingering Sex Toys
50%
The club
"Okay ladies," Missy said to her guests, "relax and get ready because I have a very special treat for today's meeting!" "What is it?" and excited Jayne asked while removing her sweat shirt and jeans. "Now you know better than to than that" Missy replied with a... Read full Story
shemale lover 2012-05-03 4,565 Group Sex Cumshot Ladyboy fingering Sex Toys
85%
Fucked by indonesian ladyboys
this is a true story of what actually happened to me in bali When i was 17 i was on holiday in bali, indonesia. i'd only had sex once prior, with a genetic girl, and i barely managed to get hard and wasn't able to cum so i knew pussy wasn't for me. i had been clubbing several tim... Read full Story
shemale lover 2014-09-17 61,134 suck Bareback Asian Ladyboy ass fucking
80%
My Sex Change
It was the day I had been waiting for. My bags all packed, two years of saving and working hard and I could finally go on my round the world trip. I said goodbye to my friends and family and checked myself onto the plane. First stop; London. With my final waves and promises to return with present... Read full Story
shemale lover 2012-04-01 4,311 sex change jerking crossdressing
100%
First Time Out
I'm so excited and want to relate this 100% true story quickly while it's still fresh. Please forgive any typos. [My background: Age 48. Closet dressing in earnest for 15 years. Began with slips stockings and nighties but have collected extensive full wardrobe and accessories over time. Boobs, wi... Read full Story
shemale lover 2012-10-23 3,344 sucking cum Sex Toys
100%
TG girlfriend is my new neighbor
With Christmas and New Year’s over, the weather here in Florida has become cooler, 45 degrees last night and it will be in the mid-sixties for the rest of the week. We live in a sub-division right off the waterway, very private. My neighbor usually comes down around Christmas and stays until tax ti... Read full Story
Jon Paul 2022-01-17 4,124 Big Tits Bareback Creampie Shemale Fucks Guy Big Cock Asian Guy Fucks Shemale
100%
Debbie Part 8
Moira sat in her booth at the entrance to the subway station and saw people pass by. She sat there every day selling tickets, and although several thousand people passed her during a shift, she could now recognize many of the regulars and she even knew when to expect them. It was now almost 9 o'cloc... Read full Story
shemale lover 2011-12-23 7,321 transgender toys bondage and discipline heavy
85%
A very hot encounter
I've had been feeling way too horny for days; masturbating every night to shemale porn. I've always loved transexuals. There's nothing better than a very hot body with a fairly large cock to be sucked and drained of hot cum. There's something even kinkier for me about a top shemale. I imagine that c... Read full Story
shemale lover 2012-07-08 4,641 anal Cumshot oral Sex Toys spanking
91%
Aby my trans daughter
I am 50 and great shemale fan. I met Aby through PlanetRomio during covid lockdown. I was alone at home that time and i was searching for some good trans or shemale. So Aby so my profile and sent me message. I immediately replied. we exchanged our contacts and then shifted our chat to Whatsapp. ... Read full Story
Stud4Shemale 2022-01-03 4,289 Crossdresser Cumshot Bareback Shemale Fucks Guy Blowjob Big Cock Asian Guy Fucks Shemale cum in mouth
100%
Crossdressing in a Hotel
Jamie was feeling excited as he entered the hotel room. He had been looking forward to this for weeks, and now he was finally here. He had dressed himself up in sexy lingerie, and had brought his toys with him. He had a normal dildo, a big dildo, a normal plug and a very big plug, and plenty of lube... Read full Story
Fischermensfriend246 2023-01-11 4,644 Crossdresser Amateur Bareback Blowjob Big Cock dildo Lingerie Interracial Sex Toys Ass to Mouth webcam webcams
77%
Allie's Encounter on Craigslist
Let me start off by saying this is a 100% true story. I know there's some that will try and pretend to be real but are in fact not. There's no real way for me to prove it, but nonetheless I just wanted to share my experience. About a week ago I posted an ad on craigslist "19 y/o Asian CD loo... Read full Story
shemale lover 2012-10-16 4,876 Fetish Sex Toys crossdressing
90%
Thai Ladyboy
One year ago, when I was 19 I went back to Thailand. The year before was to see the sights and explore the country, the second was more exploring and more fun, the third and final time was to get with as many ladyboys as possible. I had always been curious about trans women. Im not attracted to ... Read full Story
BEN437 2018-11-19 13,336 Teen (18+) Amateur Cumshot Bareback Creampie Blowjob Big Cock Asian Ladyboy domination Guy Fucks Shemale cum in mouth
100%
Thai Ladyboy
One year ago, when I was 19 I went back to Thailand. The year before was to see the sights and explore the country, the second was more exploring and more fun, the third and final time was to get with as many ladyboys as possible. I had always been curious about trans women. Im not attracted to ... Read full Story
BEN437 2018-11-19 5,065 Teen (18+) Amateur Cumshot Bareback Creampie Blowjob Big Cock Asian Ladyboy domination Guy Fucks Shemale cum in mouth
80%
How it started
What got me started off watching shemale porn was actually meeting a very beautiful shemale at a beach party. I already knew she was a guy but she was so beautiful. So at one point I asked her if she wanted to go for a walk and after a few minutes and let her know that I was down. Her response was ... Read full Story
PNPFUCKBOY 2019-02-12 11,863 Teen (18+) Small Tits Crossdresser Amateur Big Tits Outdoor Latina Bareback blonde Big Cock Ladyboy domination Guy Fucks Shemale Interracial Sex Toys Mature Homemade Ass to Mouth
91%
My Seductive Secret (True Story)
During my childhood, me and my brother used to play with two other boys who were our neighbors every weekend. One day we decided to wrestle, and I took on the youngest one, (he was about 2 years younger than me, like my brother) and we wrestled in the shed while my bro and his bro (who was my age) w... Read full Story
Chickzdigmeyup 2019-06-18 14,044 Stockings Teen (18+) Small Tits Crossdresser Cumshot Outdoor Masturbation Bareback Fetish Blowjob Big Cock Lingerie domination Sex Toys Homemade cum in mouth
85%
My Orgasm at work
I finally found my sexual fantasy come true at work. I always fantasize about one of my female co-workers (and sometimes all of them) dominating me, pegging me, brutalizing me. That every time they walk by my office, they would pour their coffee on my floor next to my feet and i'll get on my knee... Read full Story
Chickzdigmeyup 2019-06-21 6,945 Teen (18+) Crossdresser Cumshot Latina Bareback Fetish Uniform Lingerie domination Sex Toys
40%
vince
been gang banget by a group of bikers on my way to vegas..it was like 2.15 am when i pulled of the 15fwy to take a piss because it was hot and i was driving naked got out it was a dirt road and i walked to the bushes and started pissing when all of a sudden a bunch of bikers were rite at my truck i... Read full Story
ima satisfer 2020-06-03 4,148 Group Sex Outdoor Bareback Blowjob Big Cock gangbang Interracial Sex Toys cum in mouth vegas gang bang
100%
TO BE OR NOT TO BE – PART 6
TO BE OR NOT TO BE – PART 6 by Spanky de Bautumn Part 5. Sunny and Antonio got frisky at the bar, Sunny moved in with Mel and Shari, and opening night was a success The only other dress that I brought was one that I hoped I would get a chance to wear but didn't think I would. It was a black ... Read full Story
SpankydeBautumn 2021-02-26 2,438 Crossdresser Cumshot Masturbation Bareback Creampie Blowjob Big Cock Lingerie Guy Fucks Shemale cum in mouth
50%
My friend Barbara,
My friend Barbara, I look forward to welcoming Barbara. She is a lovely brunette with blue eyes who likes to make love without taboos. She knows how to bring our fantasies to life by imagining exciting role-playing games. - You're going to fall in love when you discover my underwear, she assur... Read full Story
sandratvtg 2024-07-04 750 Stockings Bareback Fetish transsexual Lingerie Sex Toys travesti Vintage rosebud plug gonflable gode xxl
66%
She-Male Pimp Daddy
I’ve been working the streets for a long time and I know all the ends and outs of the flesh market. I have six she-males that work for me and I get 50% of everything they make plus all the sex I want, any time I want it. I make them work seven days a week rain or shine. I buy their clothes ... Read full Story
shemale lover 2012-03-23 3,499 anal blonde cum Asian Sex Toys
42%
Black Man Becomes A Sissy Maid
My name is Anderson James Crawford. I'm a big and tall young Black man living in the City of Ottawa, Province of Ontario. I presently attend Carleton University, where I'm studying Criminal Law. I originally hail from the City of Atlanta, Georgia. Yeah, there are African-Americans living in the Conf... Read full Story
shemale lover 2012-07-01 4,070 Cumshot oral Sex Toys crossdressing
88%
Feminized by My Girlfriend
About 6 months ago I joined a gym because I have never had a very masculine body and now that I just turned 21 it was time to finally get off my butt and try to build some muscle. That is where I met my girl friend Brook who stands 5' 9", has a fantastic body and a gorgeous face. She looks like... Read full Story
shemale lover 2012-07-14 16,532 Fetish oral Sex Toys feminization
100%
A Weekend Together Chapter 1
My fiancée and I, decide one weekend to indulge in my fetish of cross-dressing. We rented a hotel room down town across the street from the local gay club for Friday and Saturday night. I checked in when I got off work Friday afternoon upon entering the room I stripped of my male clothes and ... Read full Story
shemale lover 2012-07-23 3,818 Fetish oral Sex Toys crossdressing
100%
Booty call :)
Your cock pounds my ass harder, my cheeks rippling with every deep thrust you give. The sounds of our moans and your balls slapping as you fuck me hard is suddenly broken by the ringing of your phone........... And you wake up. It's 2:30am and I've just finished work. As arranged, I'm giving... Read full Story
BalkanLoco91Ri 2019-08-26 5,233 Teen (18+) Amateur Cumshot Masturbation Bareback Creampie Blowjob Big Cock domination Sex Toys Homemade pov Ass to Mouth cum in mouth
90%
Saving My Marriage
I love to write Erotica. For story requests please send me a private message or email noirenoire10@gmail.com It was our anniversary. Today made five years that my wife and I have been married and we were taking a road trip to celebrate. I chose our destination but I let her choose all of our a... Read full Story
therefill05 2021-02-16 6,103 Cumshot Bareback Creampie Shemale Fucks Guy threesome Blowjob Big Cock Ebony domination Sex Toys cum in mouth
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 4,520 Bareback threesome Blowjob blonde Big Cock Sex Toys Ass to Mouth
100%
First Date With Daddy
My Dream Date. It hasn't happened yet, but a girl can hope, this story is very short story based on my fantasy's. It was Sunday night and I had my first date lined up with daddy. We hadn't met, but we had spoken online at depth and exchanged numbers. I had sent him a couple of pic... Read full Story
SEXYBADGIRL 2023-03-17 5,037 Crossdresser Bareback Creampie domination
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 7,260 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
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 4,631 Group Sex Cumshot Bareback Shemale Fucks Guy Blowjob Big Cock gangbang domination Sex Toys Mature cum in mouth shemale + shemale
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 3,969 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
91%
Chicago TG Romance
Most transgendered girls I have met want to be treated and romanced just as a normal girl would. Only in the height of passion should your animal instincts take over. I was in a Las Vegas club earlier this year and had great conversation with some tranny women. I was instructed if I wanted to meet s... Read full Story
Jon Paul 2018-06-04 7,959 Cumshot Bareback Blowjob Asian Ladyboy
96%
Family Frolic
FRIDAY My sister and her husband wanted to take a few weeks off in the sun and asked me to look after their kids for a while. I'd move out of my tiny apartment and into their house for the duration. As I was still living off my severance and they had a nice spread with an indoor pool and a h... Read full Story
shemale lover 2012-01-14 30,939 strapon porn
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 33,779 Teen (18+) Crossdresser Cumshot Masturbation Bareback Shemale Fucks Guy Fetish Blowjob Big Cock Ladyboy Lingerie domination Homemade Compilation cum in mouth shemale + shemale
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 14,096 first time Teen (18+) Amateur Group Sex Big Tits Cumshot Outdoor Bareback Blowjob Big Cock Asian lesbian public place
100%
Wet & Messy Sex
It was the text I'd been waiting for for ages. 'I'm back.' it said. Anish, one of the kinkiest guys I've ever met had finally decided to return to his holiday home, just a few minutes away from where I live. He's a well off Asian businessman and has a lovely place to entertain. It's been a while sin... Read full Story
kiwicd 2022-04-27 3,450 Crossdresser Amateur Cumshot Creampie cum in mouth golden shower
100%
Don't Avoid Daddy
It feels like I haven't been used in ages. I'm too much of a scared sissy. I find guys from all over, talk, email, text sometimes. But when it really comes down to it I get too scared. I've been with this guy before, his cock is soda can thick and he's really rough. The day after my first encounter ... Read full Story
shemale lover 2012-10-23 5,827 Cumshot oral sex deepthroating
66%
First Tranny Experience_Part 1
I met a girl that was fantastic, maybe a body builder, but she was a smoker. We became just casual friends when someone told me she was a transgender. She moved we lost touch but that short friendship introduced me to the attraction to transgendered girls. I really wanted to get to get close to some... Read full Story
Jon Paul 2018-08-06 6,946 Group Sex Bareback Creampie Blowjob Asian Ladyboy cum in mouth
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 10,950 Group Sex Big Tits Bareback Creampie Blowjob blonde Asian Ladyboy Shemale and Girl Guy Fucks Shemale Ass to Mouth cum in mouth double anal
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 6,571 Group Sex Cumshot Outdoor Bareback Shemale Fucks Guy Fetish Blowjob blonde Big Cock Asian Ladyboy gangbang
100%
TG Neighbor
With Christmas and New Year’s over, the weather here in Florida has become cooler, 45 degrees last night and it will be in the mid-sixties for the rest of the week. We live in a sub-division right off the waterway, very private. My neighbor usually comes down around Christmas and stays until tax ti... Read full Story
Jon Paul 2022-04-22 6,543 Big Tits Cumshot Latina Bareback Creampie Shemale Fucks Guy Blowjob Asian Ladyboy Guy Fucks Shemale
100%
Little cock convention
They came from all over the nation to downtown LA convention center. It was the "Little Cock Convention" I watched as men from all races and status came in. Sometimes they came with their wives,friends,Mistresses,lovers, or even their boyfriends. I was on Guard duty and walking the conven... Read full Story
shemale lover 2014-07-07 6,997 shemales hardcore sex humor
100%
Chinese Apple Turnover
I crashed harder than anytime ever in my life and my dreams were fucking vivid. I dreamt of being fucked. And of sucking huge cock and getting face fucked so hard that I was cock drunk and high from holding my breath so much. But so really horny from him doing that, so into that cock. Of Jax f... Read full Story
ASSEaster5678 2019-01-09 6,567 anal sex Shemale Fucks Guy Asian Guy Fucks Shemale
85%
Becoming a Shemale's Bitch
I just got into town and spent the whole day moving in and cleaning my new apartment. I didn't have much furniture but the place needed a lot of cleaning. I saw their was a bar a few blocks away from my apartment and decided to go out for something to eat. It was around five o'clock when I walk... Read full Story
metamafia 2012-12-21 118,744 hardcore Cumshot sucking bdsm domination
100%
I Give Up
The following story is the first of four parts of a tale that explores the theme of transformation. It is thematically similar others that I have submitted but has a larger narrative arc. I hope you enjoy reading the first portion, Act One & Two. I continue to work on better editing and someone h... Read full Story
ASSEaster5678 2018-09-14 9,089 Cumshot Bareback Shemale Fucks Guy Big Cock Ladyboy
100%
Blind Date
XtinaSmith2017 Anthony awoke to a piercing buzzing tune, a nice enough melody, but one he had come to despise shortly after he had made the mistake of making it his alarm. The culprit, his smart phone, was plugged in on the nightstand beside him and was in the process of making him gleefully aw... Read full Story
Gwapo67 2022-07-01 5,578 Bareback Creampie Shemale Fucks Guy Blowjob
100%
First Tranny Experience_Part 2
I had said good bye to her at her door and drove home. I got home at a decent hour and went to bed. The following day at soccer practice, I could only think about how wild a time we had together and began fantasizing about the whole affair when my cell phone went off. To my surprise, it was Kim s... Read full Story
Jon Paul 2018-08-06 4,796 Group Sex Bareback Creampie Blowjob Asian Ladyboy
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 5,291 Group Sex Cumshot Bareback Creampie Shemale Fucks Guy Blowjob Asian Ladyboy Guy Fucks Shemale cum in mouth
33%
Duel With the Devil, Chapter 20 of The Greatest Liar
Duel With The Devil This is a work of fiction. All characters (including the narrator), celebrities, places, residences, neighborhoods, restaurants, legal agreements and proceedings, events and incidents are either the products of the author's imagination or used in a fictitious manner. Any r... Read full Story
the greatest liar 2023-07-19 4,103 anal Bareback Creampie Ebony Guy Fucks Shemale post-op celebrity post op sex