Found on AskReddit.
1. His orgasm was like an epileptic convulsion.
“His orgasm was like an epileptic convulsion. If he were on top when he came, he would lose all control, fall and flop about like a fish. It was as dangerous as it was a turnoff.”
—AmazingGraced
2. He bit my clit. Hard.
“I’ve said this before but he bit my clit. Hard.”
—Dial-1-800-ANGEL
3. He had a micropenis. I had no warning.
“He had a micropenis. I had no warning.”
—JezebelleFiona
4. Humping a snake would have been hotter.
“I think he was trying to be a sexy snake of something. When he was moving down from my face to my twat, he kept swaying side to side in some fashion that I think he thought was sexy. After that the oral was bad, his dick was about an inch wide and maybe four inches long, didn’t feel much. I think humping a snake would have been hotter.”
—AugmentedOnionFarmer
5. He proceeds to make his cats ‘talk’ to me in a high-pitched voice for an uncomfortable amount of time.
“I have plenty of ‘bad sex’ stories, but this is my favorite: It was my first time hanging out with this guy I met online. My car was in the shop so he picks me up and we go out. We have a bite to eat and he seems like a pretty chill guy/not a psychopath, so we head back to his house. As soon as we walk through the door he tells me that he needs to introduce me to his cats. I like cats so I thought it was kind of sweet… But then he gets real serious and tells me that if his cats don’t like me he’s taking me right home. Alright, fair enough…? Then he proceeds to make his cats ‘talk’ to me in a high-pitched voice for an uncomfortable amount of time. Like I said, I love cats but this was awkward, not to mention a major mood killer. Apparently the cats approved, because we ended up in the bedroom….
…and that’s when I broke his dick.
The car ride home was uncomfortable, to say the least.”
—a_tiny_bug_irl
6. He’s still wearing his ribbed tank-top. And his socks.
“When I was about 13, I had a huge crush on this guy. He wound up dating my cousin, and my best friend, all while ignorant of my huge crush. He moves, and we really only vaguely connect back on Facebook. Until one day he messages me, saying he’s going to be in the city I had recently moved to for the weekend, and he wanted to meet up and get some drinks.
Long story short, the next night I’m in his shitty motel room, having sex with this guy I’d been in love with ten years before, and I realize something. He’s still wearing his ribbed tank-top. And his socks.
Not to mention, he’s really not very good at all.
My 13-year-old self was extremely let down.”
—OpheliaDrowns
7. Diarrhea pours out of me onto the bed mid-pounding.
“I’d been a bit sick for a couple of days beforehand. Just a cold; some lightheadedness, a bit queasy, but I was getting better. We’re having missionary sex with my legs wrapped around him. He’s bouncing on me to go all the way in and out quickly each bounce.
I’m feeling gassy, trying to enjoy the sex without my body distracting my hormones too much. I figure a fart isn’t too bad but I still work to hold it in for the sake of sexual atmosphere. Then one of his deep thrusts knocks away my control.
Diarrhea pours out of me onto the bed mid-pounding.
Oh god.
.
…Oh god…”
—noisypeach
8. Thought my clit was going to be disfigured for life.
“The worst sex I had didn’t involve penetration but it was oral sex. I was on the receiving end and this guy was being really rough. I tried to tolerate it but after just a minute I had to stop him. What was he doing? Chewing down there? Sucking the life out of my clit? I never felt anything like it but it sucked.
Whatever it was he did had my clit swollen up 10x its normal size. Like it was flowering out of my labia like a balloon. I couldn’t wear pants. Took a sick day from school the next day since I couldn’t get dressed and even walking was making me miserable. Thought my clit was going to be disfigured for life, but it went down in a few days.”
—Yogadork
9. After maybe 2 minutes in, he came all over my leg. Didn’t even get to the penetration!.
“Guy was grinding and rubbing on my leg kissing me. After maybe 2 minutes in, he came all over my leg. Didn’t even get to the penetration!”
—MotherGaysha
10. After about five minutes he abruptly stopped and said, ‘I finished, like, a while ago.’.
“After about five minutes he abruptly stopped and said, ‘I finished, like, a while ago.’
I was like, ‘…what?’”
—jilliefish
11. He whispered ‘I have a penis!’ into my ear.
“Asked my shy boyfriend to talk dirty to me during sex, and after getting him going with all the filthy shit I could think of, he moaned, grunted, worked up the courage and whispered sexily and in total earnest, ‘I have a penis!’ To be fair, this is totally not the worst sex I’ve had. A good in-the-act laugh, however unintended, can be fun. But it’s still one of my favorite stories.”
—isladecuba
12. I ended up covered in puke and blood…and it wasn’t even my own.
“The sex was pretty meh beforehand but really took a turn when he puked all over me, I jumped up and my elbow connected with his lip busting it open. So not only did I have unfulfilled and unsatisfactory sex, I ended up covered in puke and blood…and it wasn’t even my own.”
—RKola
13. He was done in three thrusts and obviously used a too-big condom as he LEFT IT INSIDE ME!
“I’d been chatting to a guy online and discovered that he literally lived about 4 doors down from me, so we decided to hook up. I was 18 and still living with my dad, so we figured his place since he was 26.
I wander round, he answers the door and we head straight to the bedroom. He undresses and is already hard and ‘suited up,’ which really should have been my first hint that it wasn’t going to be fantastic. But oh well, I’m horny and fairly inexperienced, so let’s go.
Well, he yanks my skirt up and just goes right in, no foreplay, nothing. Three thrusts later as I’m still trying to work out what the fuck is happening, he abruptly stops, pulls out and says, and I quote here, ‘You’re obviously not that into it. You should just go home. Now, because my mum will be back any minute.’
Whatever, I am totally done here even without him mentioning the m word, so I don’t even stop to put my underwear back on, just walk out the door. A few steps into my walk home I’m thinking it feels a bit weird down there, so I reach down and pull out… a condom. A FULL condom. He was done in three thrusts and obviously used a too-big condom as he LEFT IT INSIDE ME! Then tried to cover up his slight issue with premature ejaculation, by claiming I was the problem.
0/10 never again.
TL;DR: He came in three thrusts and left the full condom inside me…”
—tigerjess
14. He was not well endowed. Look at your pinky.
“I am not a size queen by any means but, sex is not just about penetration. if you aren’t gifted in some areas, be willing to participate in others.
He lived across the hall in rez, he was funny, we flirted, we hooked up. he…was not well endowed. look at your pinky. he also wouldn’t do any foreplay. nothing. not even fingers. then he pulls out FUCKING Magnums. and this is when I knew I was just drifting down the river of denial and my final destination would be sad vibrator orgasm city. so, no foreplay, way too big condom, I try and say I really just want to suck him off, try to save the evening and make something of it. NOPE in he goes! Three thrusts, tells me I’m too loose, I must be a whore. so I noped out of there.”
—Zorrya
15. I got to walk home with toilet paper shoved up my nose.
“I was getting face fucked in the shower when the guy got a little overconfident and slammed my head down hard onto his dick. My nose slammed into his pubic bone and when I moved my head back blood was pouring out of my nose. Needless to say, he made a quick excuse of being tired and I got to walk home with toilet paper shoved up my nose.”
—gaybadger
16. I didn’t cum. I cum if you look at me right, so that says a lot.
“He wanted to watch anime before and after. His room and place was filthy and I got no foreplay. He had a big dick but no clue how to use it and finished early. I didn’t cum. I cum if you look at me right, so that says a lot. I left as soon as it was polite.”
—mistressfluffybutt
17. At one point he whispered, ‘It hurts more than you thought it would, doesn’t it?’
“The first time. He was 8 years older than me and basically talked me into it when I was in a deep depression. I was dry af and it really hurt and I started crying during the sex (don’t worry, it didn’t ruin things for him). Heh. At one point he whispered, ‘It hurts more than you thought it would, doesn’t it?’ Bonus lame point: when he was dropping me off, I was all ‘does this mean I’m not a virgin anymore?’ Also he didn’t call me after. Of course.
Double bonus: He was a pedophile who later did time for child porn charges. He liked ’em young! (I was 17, so legal in my state, but looked younger). One of his friends even said I was older than the girls he usually went for.”
—Paisley_hippo
18. He leaned over, whispered ‘I love you,’ and I felt a wet spot on my leg.
“Clingy not-quite-boyfriend, wanted more than I did out of the relationship. One afternoon we were hanging out, he kept edging closer to me. I wasn’t sure if he was cold, wanted a cuddle, or what; he never said a word, just kept staring straight ahead at whatever PG-13 teen movie we were watching and sitting uncomfortably close. Every once in a while he’d sort of rub on my leg; I thought he was just trying to get comfortable. Nope.
He leaned over, whispered ‘I love you,’ and I felt a wet spot on my leg.
We didn’t talk much after that day.”
—my_random_thots
19. When I didn’t cum he said, ‘You came close though, right? That’s what counts.’
“There was this really gorgeous Brazilian guy on the soccer team at my college. We knew each other and were really friendly for about a year and a half before things happened. He came over, and I was really, really excited to get with him. He stumbles in a bit drunk, but still smiling and he seems excited too. We start making out on my bed.
Clothes come off and he starts eating me out. I lay back and relax, closing my eyes and focusing on the sensation….except it feels….off? Like, really blunt and not enough pressure or something. I look down and see he’s closing his eyes just drunkenly dragging his face back and forth over my entire pussy. Real turn off.
I should have sent him home, but I honestly didn’t even think about it in the moment. He somehow gets it up and after like, two minutes he’s apparently done and jumps off my bed, starting to put his clothes on. I’m really disappointed, I ask him ‘you’re leaving? Really? At least help me finish…’ And he responded with ‘Oh, my friend is waiting for me. You came close though, right? That’s what’s counts.’ And walked out.
Texted my roommate that she could come back not even 20 minutes after I let him in the building. Really embarrassing.
Fucking jocks.”
—TractorPants
20. We had awkward sex while his roommate cried next door.
“I’ve had lots of bad sex, boring or tiny penis you can’t feel at all… but the worst was when I started dating this guy who was older than me and a ‘scientist.’ It sounded so cool to me that I put up with his weirdness. He lived in this house where he rented a room and had weird roommates. One roommate he told me was morbidly obese and never left the house. I never met them. Anyway, dude I was dating had a big schlong but had zero idea how to use it. His tiny room was mostly a computer and clothes, and he slept on a foam sheet on the floor. He would only have sex missionary and super slow. I was miserable each time. But the worst sex was we were slowly going at it and I start hearing this weird sound from outside. Sounded like a cat meowing, or maybe a baby crying. I ask him if he hears it and he says “oh that’s bob (roommate), he’s changing the dressings on his legs and it’s so painful he cries while he does it.” Didn’t stop his weird slow thrusting at all. I noped out of there. Ended up dumping him for a multitude of reasons a little later on, but that awkward sex while his roommate cried next door will always be remembered.”
—dat_taffy_butt
21. He had talons for nails, so everything hurt.
“Ughhhhhh! this guy. his penis was long but quite thin and he just didn’t know what he was doing….He had talons for nails, so everything hurt.”
—LadyGaga_luvs_U
22. I wound up just hurling all over him.
“My boyfriend and I have been into BDSM basically since the day we got together. He’s usually a dom, I’m usually a sub, and we do the Daddy Dom/little sub kink. This was a couple of years ago, so we couldn’t have been together long. He made me a grilled cheese and homemade tomato soup for dinner (I like comfort food), and I was very full. We were horny little assholes, so we fucked like an hour later. At the end, he had me get on my knees and be ready for him to cum in my mouth. Before I could swallow, I had to hold it on my tongue to show him how much cum I could take. In a moment of horrific inspiration, he decided to add on to the cold load on my tongue by spitting in my mouth. I immediately projectile puked tomato soup, grilled cheese, cum, and spit. In a moment of panic, my boyfriend shot his hands out to catch the puke mid-air and I wound up just hurling all over him.
As soon as I realized what I did, I screamed and ran to the bathroom and sobbed for like half an hour while he cleaned up. Eventually I let him into the bathroom, confident he was going to dump me and tell me to get out. Instead he sheepishly apologized for being a huge idiot and we had a great laugh about it.”
—smutwitch
23. I accidentally pushed him into the pond.
“Was at a party at a friend’s house and hooked up with a guy in the yard out back by the koi pond. A cop car with its siren on drove past (turned out to be something totally unrelated) and we freaked out thinking we’d get busted for indecent exposure or something. We were having sex with him sitting in a lawn chair and me straddling him, and in my hurry to get off him and look like we weren’t doing anything I accidentally pushed him into the pond.”
—Petronella23 
Read this: 23 Men Reveal The Absolute WORST Sexual Experience Of Their Lives