Sort by
Relevancy

Free Stories

78%
A Little Girl Forever
Since I was a little girl I dressed in my sister's clothes, she knew it and she kept clothes for me and sometimes she bought clothes thinking about me. She was my accomplice and still is. When I was alone I dressed totally as a woman and I felt totally satisfied and realized as such, this included m... Read full Story
Mabel Cecilia 2019-05-06 8,037 Small Tits Crossdresser Amateur Cumshot Latina Masturbation Creampie Blowjob blonde Lingerie Shemale and Girl Guy Fucks Shemale Sex Toys Mature self sucking Solo Shemale cum in mouth double anal shemale + shemale
100%
First Cross-dressings Loosing Anal Virginity
It happened after a month of me blowing that guy twice...I mean I was so damn excited and was craving for his cock....I was blowing him every weekend in his car after the school...his cock was almost 7 inches and was so thick and that I like so so much the gagging he was giving everytime, that chock... Read full Story
Trapbomb1 2022-07-29 6,761 Teen (18+) Crossdresser Bareback Creampie Blowjob Big Cock virgin virginity sissy cum in mouth double anal sissy slut virgin ass
100%
Playfull Sexy Shemale LindaTgirl
The overwhelming passion will start. When you date me... it will all start with kisses and wrapping with my legs around your body and showing of her gorgeous smal tits.The, while sitting on your lap I will whisper in your about what will be next.. About what turns me on... about sucking, licking,... Read full Story
TS-Linda. 2022-02-21 2,523 Small Tits Amateur shemale Lingerie escort money latina ass PAWG Pawg Tranny lindatgirl
44%
First time with a shemale
I must have been 16 back in the day, but I always looked older so it didn't really affect anyone's judgement in the sex world that I had loved since I can remember jerking off for the first time. I was walking the streets of Amsterdam that day, the Red light Disctrict looked like paradise on earth,... Read full Story
shemale lover 2012-02-14 7,154 first time Stockings Small Tits
0%
Looking-Glass Ladyboy
I was taking a walk to stay--all right; I'll admit it--to get in shape, when I saw the "Going Out of Business" sign in the second-hand furniture store a block north of my condo. I wasn't in the market for anything, new or used, but I can't resist a bargain, and what was better for finding ... Read full Story
shemale lover 2011-10-29 7,650 asshole Fetish Ladyboy
72%
ACROSS THE STREET AND TWO DOORS DOWN by Spanky de Bautumn
Jamie knew he was different. He didn’t fit in with the other boys, but he didn’t feel like he fit in with the girls either, he just knew he was different. He wasn’t into dolls or balls. He was the smallest boy in his class and more than half the girls outweighed him. But the one thing he had going f... Read full Story
SpankydeBautumn 2021-01-29 11,372 Teen (18+) Small Tits Crossdresser Fetish Blowjob Lingerie Guy Fucks Shemale cum in mouth
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 7,042 Cumshot suck Shemale Fucks Guy Ladyboy ass fucking swallowing
80%
intimate Cousins
My favorite cousin and first lover, Billy, was just released from prison and I was anxious to see him. I am ecstatic that he is out, and I am thinking about all the past fun we had as I prepare to revisit those good times. Tommy knows all about my relationship with Billy and he understands my need t... Read full Story
Regina10 2022-05-13 6,059 Stockings Crossdresser Cumshot Masturbation Bareback Blowjob Big Cock Ladyboy Guy Fucks Shemale Ass to Mouth cum in mouth double anal
94%
Sissy Slut: Gang Favored
I confess I am a nymphomaniac shemale slut who loves being the object of a man’s desires. That's why I was out here with these hookers trying to hook up with somebody to have sex. I'm either having sex or I'm thinking about having sex most of the time I like being a honey. I love having sex with men... Read full Story
Regina10 2021-03-02 7,501 Stockings Big Tits Cumshot Bareback Fetish Blowjob Big Cock Ladyboy gangbang Guy Fucks Shemale cum in mouth double anal
80%
Buffy the Shemale Vampire Slayer Part 13
Buffy's cock slipped out of Baubo's mouth, and she licked the smooth skin of the stiff, elongated shaft with her tongue. Baubo had no hands, but, even so, she was a superb cock sucker. More than once, she brought the Slayer to the brink of orgasm, then backed off, letting Buffy's sexual passion abat... Read full Story
shemale lover 2011-08-23 3,763 Masturbation pussy shemale
100%
Sweet Sherri
"The fuck you want," the girl hissed through her teeth. Well, it's hard to say. For one, this was the one night of the week at the particular club that was tranny night. Unless the lucky woman was either a straight freak or had been exposed to the scene, there weren't too many people wa... Read full Story
shemale lover 2011-10-31 5,550 Big Tits transsexual big ass
100%
Clara Bow's Academy for Ladies
Peter had had no choice in the matter from an early age. As he car drew up to the huge ivy clad castle-like building, having entered through electronic gates in a ten foot wall, he felt doomed yet excited. His cock was erect in the tight panties his Stepmother has chosen for his introduction, his an... Read full Story
shemale lover 2013-03-27 5,032 Teen (18+) Small Tits shemale public softcore
100%
delicious virile male flesh
Tasted delicious virile male flesh… The breeze caressed my swollen nipples giving me pleasant shivers. The two glasses of Riesling had also contributed to my excitement. My crotch was burning as if the disappearing sun had blown all its thermal energy into me. Under my fine lace panties, purple o... Read full Story
hippocampus_171 2023-04-23 5,000 anal Small Tits Amateur Creampie Blowjob Mature small cock big ass feminisation cum in mouth gaycd virile
100%
Uncle sweet Lover
Uncle Barney called me this morning and wanted me to keep my evening free. He wanted to meet me at the motel with a surprise for me. I was so excited and could hardly wait. I had to decide on something to wear, but when I thought about it, I realized that I wanted to wear something special. He would... Read full Story
Regina10 2024-02-19 4,771 anal Crossdresser Big Tits Creampie Fetish Blowjob Big Cock Ebony Ladyboy Guy Fucks Shemale Mature big ass femboy
84%
SUMMER VACATION by Spanky de Bautumn
In our house, it was a well-known secret that my mother kept her change in the top drawer of her dresser. The same drawer she kept her slips, chemises, panties, and all other satin, nylon, or lacy ladies undergarments. During the summer, my brother and I would run to that wondrous drawer when... Read full Story
SpankydeBautumn 2021-01-22 12,655 Small Tits Crossdresser Cumshot Masturbation Fetish Blowjob Lingerie Shemale and Girl cum in mouth
100%
Male or Shemale, Still a Slut
Part 1 My name is Brandon. I'm 18 (still in high school), 5'5", white with black hair, and rather feminine. I'm really slim with barely any body hair. All this has combined so that I'm not so popular with the ladies, which sucks cause I am one horny son of a bitch. Luckily, I'm rather fond ... Read full Story
shemale lover 2012-12-20 9,312 Cumshot sucking blonde ass fucking Guy Fucks Shemale
57%
Amsterdam shemales
This was a few years ago I decided to go to Amsterdam and see if I was gay . Booked A weekend and went drinking,went around the the red light district see what girls and others were around. Went to this beautiful brunnett girl from Bulgaria with big tits, she started sucking me off but I could not ... Read full Story
Saoirse1973 2017-06-28 16,805 Shemale Fucks Guy Blowjob Ebony Interracial
100%
Regina’s Double threat.
Hello guys, I recently ran into a former hater who was no longer the hater I had met years earlier. In fact, he had only treated me so horribly because of his own inner dark desires. When we met a few years ago at one of the clubs, he had been very abusive to me. He went out of his way to say hurtfu... Read full Story
Regina10 2022-02-08 3,069 Big Tits Cumshot Bareback Creampie Fetish Blowjob blonde Big Cock redhead Guy Fucks Shemale Ass to Mouth double anal
94%
Tortured by the T-Girl Tutor
Duncan didn't quite know how to handle it. He'd planned on a quiet Winter Break. Sleeping til noon, watching too much television and eating tons of junk food. That kind of stuff. He had a whole two weeks off from community college. At school, he was an outcast. They say life gets better after hi... Read full Story
shemale lover 2012-12-18 34,034 Big Tits shemale Big Cock Lingerie domination
100%
Double Anal With a shemale
....He answered the door and there she was beautiful as ever. He had just paid 500 dollars to have a transsexual e****t come directly to his door and greet him. She had on a long pea coat and thigh high boots. When she took the pea coat off all she had on was a one piece swimsuit. Her tits were a 36... Read full Story
shemale lover 2015-04-29 5,388 tranny suck Big Cock ass fucking dp precum
73%
Shemale Masturbation Tube Just For Me
I was just coming back from the gym - damn, lights on the parking lot were flickering again - when I heard this noise. I ran and saw a shady looking guy pointing a knife at a woman trying to unlock her car. "Hey", I yelled, "I'm calling the cops and a dozen big dudes are going to be h... Read full Story
shemale lover 2016-02-24 5,815 sucking cum nipples
75%
Super Shemale Tube At The Waiting Line
The restaurant was crowded - everyone in Boston wanted to be there, and I waited for an hour at the bar, hoping to get a table for one. But was I watched my chances of having dinner crumble to dust and glanced at Super Shemale Tube on my phone's browser, a girl sitting next to me asked "Hey, yo... Read full Story
shemale lover 2016-03-14 6,662 anal cum big ass
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 9,364 sucking cum gangbang
82%
Halloween Double Cross
It all started off so innocently... My wife Jo, tall, slim, blonde, aged 40 with 34DD tits and the sexiest big ass imaginable, works as a doctor. Her hours are long and arduous. She often comes home completely worn out. Only during the holidays does she tend to recover her sparkle. She is gorgeou... Read full Story
ASSEaster5678 2018-10-29 11,303 Shemale Fucks Guy sissy Halloween
42%
Shemale Free Chat And Sex Adventures
It was another day at work at the mall. Being a security guard wasn't exactly the most exciting job in the world: I'd sit all and maybe get a few calls about some punk kids trying to steal DVDs. I felt like my talents were wasted there - I used to be a competitive bodybuilder, evening getting into f... Read full Story
shemale lover 2016-04-24 3,843 anal transsexual ass licking
100%
First Time With Shemale
For as long as I can remember, I've preferred my chicks with dicks. There's something about a sexy babe with perfect makeup and hair and a cock that just turns me on. Maybe that makes me a pervert - I don't care! I remember I was just out of high school, 18, the first time I made it with a tranny. S... Read full Story
shemale lover 2011-08-26 3,808 anal Creampie shemale
85%
Alpha Gamma's Secret
Molly woke up to the sound of her alarm clock beeping. She opened her eyes slowly and looked at the time. It was 7:00 AM. She groggily reached over to shut it off, pulled away her blankets, and stepped out of bed. She walked from the bed room which she shared with her sorority sister Gina to the ... Read full Story
shemale lover 2011-11-02 4,522 Small Tits asshole transsexual
88%
Girl from Uncle
Tonight, I have to tell it all. It’s no secret that my uncle and I had a very special bond he had been eyeing me with those adventurous eyes from the time that I was 14 years old. And frankly I enjoy his ogling. I could feel my nipples get so hard when he looked through me with those alert and spark... Read full Story
Regina10 2024-02-14 5,206 anal Crossdresser Big Tits Bareback Blowjob Big Cock Ebony Lingerie Guy Fucks Shemale big ass femboy Ass to Mouth cum in mouth
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 12,466 anal tranny Blowjob Big Cock bj asstomouth
100%
Shemale Maid
Colleen rushed through the mansion's open gate and headed towards the main door. She opened her mini leather bag and searched frantically for her keys, although she knew she was hopelessly late. Was it her third or fourth unsuccessful attempt in a row to get there on time? Or had there been more? Oh... Read full Story
shemale lover 2011-09-13 5,140 licking sucking Big Cock swallowing
100%
Regina's scary, and sexy Blind Date
I had just finished doing my makeup, finally deciding which blush to use, and I thought I had some time for my meditation. However, Mr. Cobb was early. The gold minidress I wore showed enough legs, ass and tits to make any man horny, and the strappy tanned five-inch sandals, made me feel majestic ... Read full Story
Regina10 2024-03-18 4,605 anal Crossdresser Bareback Creampie Fetish Blowjob Ebony Guy Fucks Shemale big ass sissy Ass to Mouth cum in mouth
100%
KING OF TRANNY CHASERS ENTRY 2
LAST YEAR TO CELEBRATE MY BIRTHDAY I DECIDED TO FULFILL ONE OF MY SEXUAL FANTASITES. I HAD BEEN WITH 2 CIS WOMEN SEVERAL TIMES BUT NEVER HAD I BEEN WITH 2 TRANNIES. MY BIRTHDAY WAS ON A FRIDAY SO I SPENT THAT DAY AND THE NEXT CELEBRATING WITH MY FAMILY AND GINA..THAT SUNDAY I SET UP AND PLANNE... Read full Story
Ghostface drillah 2024-07-04 1,007 anal Amateur Group Sex Big Tits Cumshot Shemale Fucks Guy Fetish Big Cock Guy Fucks Shemale big ass Homemade Ass to Mouth shemale fucks shemale
71%
A Shemale Christmas Carol
I got a job working as a mall Santa at the local mall during the Christmas shopping season one year. It had been a real shitty year for me. My wife of almost twenty years left me for a younger man, I lost my other job due to layoffs and, on top of all that, my doctor diagnosed me with high blood pre... Read full Story
shemale lover 2011-08-28 4,534 asshole sucking Big Cock
86%
The Girl Next Door Ch. 01 by derezzed ©
Michael was your average 21-year-old college student. He was on his way home from college for summer break after finishing his finals and looking forward to a few months of relaxation. Driving home Michael reflected on his past three years of college. It had been a great junior year. He met a lot of... Read full Story
StevelovesTgirls 2019-05-27 18,079 Amateur threesome Big Cock shemale + shemale
94%
The Girl Next Door Ch. 01
derezzed Michael was your average 21-year-old college student. He was on his way home from college for summer break after finishing his finals and looking forward to a few months of relaxation. Driving home Michael reflected on his past three years of college. It had been a great junior year. H... Read full Story
Gwapo67 2022-05-13 6,770 Bareback Creampie Big Cock shemale + shemale
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 7,631 Teen (18+) Small Tits Amateur Group Sex Latina Blowjob gangbang 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 11,880 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
100%
2nd date with Latina Sissy Destiny
So this was my second time with Destiny, a really cool Latina CD/Sissy who had just turned 22. You might want to read my first goaround with her title, “Deflowering Latina Sissy Destiny” as it will give background and context here. After our first encounter, she signaled that she was definitely... Read full Story
AllenB 2022-04-05 4,082 Crossdresser Cumshot Latina Creampie Shemale Fucks Guy Blowjob Interracial cd Homemade sissy cum in mouth cum swallow amatuer cd
80%
Bisexual Black Man's Paradise
The name is T.J. Brown. I'm an engineer working at Walpole, the toughest correctional facility in the state of Massachusetts. My days are spent reading books, exercising and occasionally tussling with other workers. The facility is undergoing some expansion and I'm the lead engineer on this gig, wor... Read full Story
shemale lover 2012-06-24 5,426 big dick tranny anal sex Cumshot orgy facial oral sex
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 6,336 anal shemales Group Sex
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 5,164 Teen (18+) Crossdresser Group Sex Big Tits Bareback Creampie Big Cock gangbang domination Guy Fucks Shemale Interracial double anal webcams
84%
Lesser of Two Evils
My name is Eric. At 21, I was working as the IT guy at a prominent Caribbean cruise company. My days were usually pretty boring. Fixing computer problems were usually a no brainer for me. People are so stupid when it comes to how they use their machines that I assume there will always be a need for ... Read full Story
shemale lover 2013-03-27 22,781 hardcore Cumshot sucking ass fucking Guy Fucks Shemale
83%
Teacher Student Confidentiality
It was raining cats and dogs outside as Ms. Catherine Walker (Cat by her friends) graded her Accelerated Integrated Geometry test scores. Her was long and flowing and her sweater was purposely pulled low to embarrass the male teachers with her cleavage. Her cock twitched as she shifted her leg to a ... Read full Story
shemale lover 2012-02-11 14,000 anal Blowjob black fiction
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 11,862 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
100%
I wanna fuck almost everyday
I can't stop thinking to be Double penetrated for two men at the same time.... It makes me feel I'm insatiable gurl... Two Big cocks mmmmmmm after been fucked for so long ... I will never go back... And certainly I will totally satisfied and addicted to it...... Read full Story
Bellasohot 2022-07-13 3,823 Crossdresser Amateur Latina Bareback threesome Big Cock Ladyboy Lingerie Guy Fucks Shemale Mature Ass to Mouth double anal
100%
Couple and a Tranny
There is a saying that a single man looking for companionship and good fortune will seek someone for marriage. Lydia and I met several months ago on an online dating site. We agreed to meet at a bar restaurant for drinks and initial meeting. She was at the bar wearing a yellow sundress, white painte... Read full Story
Jon Paul 2022-09-20 5,324 Cumshot Outdoor Latina Bareback threesome Ladyboy Shemale and Girl Guy Fucks Shemale Ass to Mouth double anal
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 23,976 Cumshot Blowjob fuck fingering big boobs
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 10,968 Group Sex Big Tits Bareback Creampie Blowjob blonde Asian Ladyboy Shemale and Girl Guy Fucks Shemale Ass to Mouth cum in mouth double anal
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 33,814 Teen (18+) Crossdresser Cumshot Masturbation Bareback Shemale Fucks Guy Fetish Blowjob Big Cock Ladyboy Lingerie domination Homemade Compilation cum in mouth shemale + shemale
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 13,887 Teen (18+) Crossdresser Amateur Cumshot Masturbation Blowjob Big Cock Ladyboy Lingerie domination Guy Fucks Shemale Homemade Compilation Vintage cum in mouth
100%
Sissie Slut's Windows of Womanhood
I flash back to my first time with a grownup adult at the tender age of16 . I was so nervous now that we were here in the motel room. I was nervous for so many reasons. I lied to my family and told them I was staying at a friend’s house. Instead, I'm here with Mr. Joey in a motel room and he was my... Read full Story
Regina10 2021-02-22 6,663 Crossdresser Bareback Creampie Fetish Blowjob blonde Ladyboy Lingerie Guy Fucks Shemale Ass to Mouth cum in mouth double anal
100%
TO BE OR NOT TO BE – PART 2
TO BE OR NOT TO BE – PART 2 by Spanky de Bautumn Part 1. Sunny, Mel, and Shari learn they are going to New York to perform a play off Broadway and are really excited about it. Being a small troupe, we unseen members had to wear many hats. Unfortunately, there was just the two of us, Joe Donn... Read full Story
SpankydeBautumn 2021-02-22 3,648 Small Tits Crossdresser Cumshot Bareback Blowjob Big Cock Lingerie Guy Fucks Shemale Interracial cum in mouth
80%
The Farm
“See you Sunday, baby,” said Marcus Jenkins to his wife, Tasha. “Alright! Have a good day at work,” the wireless phone company retail store manager smiled. “Love you, Kobe! Love you, Tiara,” the wastewater plant operator said to his offspring. “Love you, too, daddy,” the youngsters rang out in un... Read full Story
Faggyboi and Puzziboi 2021-12-08 5,525 Teen (18+) gangbang Guy Fucks Shemale sissy femboy Ass to Mouth
90%
Why does cock look so good on a girl ?
Horny and looking for something to jerk off on, of started surfing porn sites looking for just the right hottie. Pornstar Christie Lee really gets my juices going so I clicked on her. I started watching the video I was familiar with and knew would get me off when I decided to check out all her video... Read full Story
Verdura08 2022-10-17 6,155 Crossdresser Amateur Cumshot Big Cock ts posing huge dildo
100%
Oneness with the bodies
many years went into just fantasizing being with shemales. I was getting hornier day by day to try it out. But being in a relationship there was hardly any room or time for it. I once experienced it in bangkok and confirmed that I really can do it and actually love it. One day suddenly it was br... Read full Story
zyankhaan786 2023-05-30 6,453 Group Sex Bareback Shemale Fucks Guy Big Cock domination big ass cum in mouth double anal
78%
First Time Having Sex With A Shemale
Ok let's begin so I was walking down the street going to the store one day I saw a woman and her daughter moving into a house they had some heavy boxes that they need help with. At first I thought she was white girl but when I got closer to them they we're Asian becuase i only saw the back and they ... Read full Story
bigtranslover 2011-05-21 14,988 first time shemales interracial sex