It's not like she didn't know how it happened. She knew exactly how it happened, and she knew exactly when it happened. To the day. To the hour.
Her college roommate Lori worked at a local haunted house back during the Halloween season. Every year, after the haunted house closes down for the season, the workers all throw a big costume party. Well, that's what they call it. In reality, it was just one big orgy. Basically, everybody shows up in costume - not the one they used during the haunted house itself. A brand new costume. Guys all scamper around the house and pick a room, then the girls just pick a room and go on in. Whatever happens...happens. A lot of people will invite friends along and nobody ever complains. Who the hell is going to complain about more women showing up looking for anonymous sex?
"You should go, Amy. You haven't been out and about since you got here. I went last year. It was a lot of fun. There's nothing like getting fucked silly by someone you've never met." Lori said.
Amy didn't need all that much convincing. She and her boyfriend split up when they left for college. She hasn't been laid since. So, what's the harm? She shows up, has a one-night stand, and that's the end of that.
Lori drove her to the party. She didn't go out of her way on a costume, and basically stuck to your standard "slutty cheerleader" costume you can buy at any cheap costume store for a few bucks. She wasn't going for originality. She was going for sexuality and ease of access. She wasn't that worried about anonymity since she knew almost nobody in town anyway, but she threw some zombie makeup on her face just to be on the safe side. Lori headed in first and that would be the last that Amy would see of her this evening. She was escorted down the hall a few minutes later.
Her escort opens the door to a dark room where it's pretty clear there's already a couple of people doing the deed.
"Oh, oh...shit...sorry", the escort said. It didn't matter. Before he could shut the door, a hand reached out and pulled Amy into the room. "It's Ok. Always room for more.". All Amy could tell was that the voice was female, and from the heavy breathing she could tell there was someone already pleasuring her.
A threesome? Amy wasn't even given the chance to wrap her head around the situation before she found herself grasping onto the couch, panties pulled aside, and a woman dressed as Harley Quinn tongue-fucking her pussy like her life depended on it. Harley was bent over on all fours and while this was going on, a guy in a Batman costume was fucking her doggy style. It was pretty obvious that Harley was experienced with women, and it wasn't all that long before her brain lost any ability to protest even if she wanted to. Harley was doing things to her that she didn't even think possible.
Amy made her way onto the couch to position herself more comfortably as Harley brought her closer and closer to orgasm. With Harley's tongue working on her clit and 3 fingers buried inside her, she came harder than her boyfriend had ever made her cum before.
When Batman pulled his cock out of Harley to go get himself a drink, they took the time to switch positions so Amy could return the favor. She had never eaten pussy before but at this point she was willing to at least try her best. Face down, ass up, Amy buried her face in Harley's pussy and did her best to mimic what Harley had done to her minutes before. And just as she was getting into rhythm...the next thing she felt was an absolutely enormous cock filling her pussy up. Holy shit this thing was monstrous. And Batman had absolutely no intentions of just easing his way into her, and began fucking her with every ounce of energy he had. She repeatedly stopped herself from eating Harley's pussy to take a deep breath, and found it very difficult to concentrate on Harley with the guy behind her fucking her so well. Harley eventually just grabbed two handfuls of hair and held Amy's head in place while the guy continued fucking her, and eventually let out a loud moan as she came all over Amy's face. It wasn't long after that that she felt the warm feeling of Batman emptying himself inside her.
Amy got up and fumbled around for the lights. When she turned the lights on, Batman was gone and Harley was gathering her belongings getting ready to leave too.
"Any idea who that was?" Amy said. She figured since it was Batman and Harley Quinn, maybe they knew each other or were a couple since the costumes were from connected comic book characters. Nope. Was nothing but a coincidence.
"Nope. No idea", Harley said as she gathered her stuff and walked out the door. "Later."
Amy took a few minutes to compose herself and process what just happened. What she thought would just be an anonymous hookup ended up being her first threesome and her walking out of the room with a sore pussy full of some guy's cum. No regrets. That was still the best she had ever had by a country mile.
It was about three weeks later when she realized that she was overdue for her period. "Fuck, I knew I should have gone for that plan B. Just my god damned luck." she thought when the second pregnancy test also came back positive. In her mind, she figured it would be best if she got it out of the way and just let her parents know. The shouting match and incessant arguing was going to happen one way or the other, and she figured get it over with sooner rather than later. Thanksgiving dinner was probably not the best time to unload that kind of news on them, but she thought it would be best to say it face to face, and that was the only real opportunity she was going to have until Christmas, and she didn't want to keep it a secret for that long.
But when she showed up back home, she realized she hadn't planned this out as well as she thought she did. Her parents were going to have a hundred questions, and she didn't have a hundred answers. When she showed up, she settled into her old bedroom and headed to her brother's room. Her brother would be more understanding. He wouldn't ask all the embarrassing questions she probably didn't want to answer. And he would be able to help her come up with at least some answers for the questions his parents were going to ask.
Then she walked in, and saw the Batman costume bunched up in the corner of his room...
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