Spider-Man, also known as Peter Parker, was out of costume, in only his boxer shorts, and sitting on a wall.  He stared at the invitation he carried, adorned with famous men and women from fiction, both the one in his hand and the one in his wife's hand.  

"...I can honestly say that I'm at a complete loss," he said after a moment.  

"A multi-universal sex party?" Mary Jane said, the buxom redhead shaking her head incredulously, her nightgown, the only thing she had on, blowing slightly in the night breeze from the open window.  

"Something weird's going on here," Spider-Man said.  "They use both my costumed name and my real name, and gave an invitation to you."  

Mary Jane frowned, looking at the card.  "Congratulations Mary Jane Watson-Parker," she read.  "You've been chosen to attend the Multiversal Sex Party!  Because of your dedication and strength even while your husband is out risking his life, at times needlessly, you have been chosen to take part in the biggest sex party in several universes to help blow off some steam.  You'll be made immune to all toxic or parasitic powers (they'll only work if you let them), you'll get no diseases no matter how much sex you have, and there will be no unwanted pregnancies.  Villains will be there, but they will be forced to behave.  No one will kidnap you unless it's part of a mutually agreed upon sex game.  All sex WILL be consensual (we are very capable of enforcing this), and rapists will not be allowed into the party.  In fact, they will suffer humiliation while you are there, all regular criminals pacified for the full duration of your stay and the stay of the other heroes in the party dimension.  Fulfill fantasies you may have had.  Blow off steam, and enjoy yourself.  When the party's over, it will all just be a midsummer night's dream that you had, as you'll be returned on the night you left, your own affection for your husband renewed by your release of stress.  All you have to do is say yes, and a portal will open for you."  

Spider-Man looked at his invitation, reading it aloud again.  "Congratulations Spider-Man, alias Peter Benjamin Parker," he read.  "You've been chosen to attend the Multiversal Sex Party!  Because of your dedication and strength, along with your kind, just heart and your loyalty to your wife in the face of many buxom heroines who'd love to bone you, you have been chosen to take part in the biggest sex party in several universes to help blow off some steam.  You'll be made immune to all toxic or parasitic powers (they'll only work if you let them), you'll get no diseases no matter how much sex you have, and there will be no unwanted pregnancies.  Villains will be there, but they will be forced to behave.  No one will kidnap you unless it's part of a mutually agreed upon sex game.  All sex WILL be consensual (we are very capable of enforcing this), and rapists will not be allowed into the party.  In fact, they will suffer humiliation while you are there, all regular criminals pacified for the full duration of your stay and the stay of the other heroes in the party dimension.  Fulfill  fantasies you may have had.  Blow off steam, and enjoy yourself.  When the party's over, it will all just be a midsummer night's dream that you had, as you'll be returned on the night you left, your own affection for your wife renewed by your release of stress, your identity made secret once more.  All you have to do is say yes, and a portal will open for you."  The arachnid-themed superhero shook his head.  "A little weird to compliment me on my loyalty and then invite me to have sex with other women."  

"Don't forget, tiger.  I've been invited too," Mary Jane said, chuckling weakly.  

Spider-Man shook his head.  "Something about this isn't adding up," he said.  "I'm guessing that the disappearance of all the metahumans has to do with this party, but why send for me last?"  

Mary Jane looked thoughtful for a moment.  "...I think we should go," she said suddenly.

Spider-Man quirked an eyebrow at her.  "Excuse me?" he said.  "Looking to sleep around that much, eh?" He grinned, showing her he was just teasing.

Mary Jane sighed, rolling her eyes.  "Look, you said it yourself: why wait until last to invite you?  Maybe the people managing this were trying to take you into account to hide something," she said.  "We both go under the guise of wanting to participate.  We... indulge ourselves, I think we can forgive each other a little infidelity this time, but all the while we work to find a way to figure out what's behind all this.  If they're benevolent, fine, no worries, we both get our jollies and go home when the party's over.  If they're malevolent, we rally the other heroes there, free them from whatever mind control they're under, save the day and go home.  Hell, there's a fantasy for me right there, to be a big a hero as you are."  

Spider-Man grinned warmly.  "You've always been my hero, MJ," he said.

Mary Jane blushed, smiling happily.  "Well, yes, but you're rather biased.  I want to do something big."  

"You do.  Every night we make love," Spider-Man said, smirking.

Mary Jane snorted laughter, turning away for a moment.  "That's too easy, I'm not gonna touch it," she said.  "Right now, at any rate." 

Spider-Man stuck out at his tongue at her, hopping off of the wall and hugging her close.  Mary Jane smirked.  "Besides, tiger.  I seem to remember you liking me wearing that Lara Croft costume last Halloween.  I'm sure you wouldn't mind peeling those short shorts off of the real Lara, now wouldn't you?" she teased, gently rubbing his manhood beneath his boxer shorts.  

Spider-Man blushed, feeling his member start to grow hard.  He cupped one of her breasts from behind, gently stroking the nipple to erectness, making her gasp with pleasure.  "And I recall you rather liking Captain America's tight abs.  Since Cap's probably there, you'll get your chance to feel them up yourself."  

Mary Jane bit her lip, shuddering in delight.  "Mmm, oh yes..." she said softly.  "The plan's a good one though, right?" 

Spider-Man nodded, gently kissing her neck.  "It is," he said.  "It makes perfect sense, and is simple enough to remember.  My wife, genius strategist."  

Mary Jane nodded, grinding her shapely rear into his crotch.  "It's settled then," she said.  "We're both accepting the invitation."  

Spider-Man nodded.   And then his spider-sense went off, just an instant before a portal appeared underneath the two of them, sucking them inside, cloaking Spider-Man in full costume and Mary Jane in a revealing version of her husband's outfit.  The athletic hero flipped in midair, catching his wife as they fell from a ceiling and then landing on his feet, the practiced web-slinger not even feeling a jolt in his ankles as he landed even with his wife's added weight.

"Wow..." Mary Jane said softly, frazzled by the fall.  

"Yeah," said a voice from behind them.  "They got all of us like that when we accepted the invitation."  

Mary Jane and Spider-Man whirled, seeing Hawkeye and Mockingbird behind them, arm-in-arm and both with wine glasses.  The two recent arrivals looked around, finding themselves in what looked like a simacularum of Avengers Mansion.  Several people they knew from the heroic community were milling about, talking or openly flirting with one another.  

"You two are the last from our world to arrive," Mockingbird said.  "Glad you decided to join us."  

Spider-Man blinked.  "This is... not quite what I expected."  

Hawkeye snickered.  "Expecting a huge orgy, webhead?" he said.

Spider-Man rubbed the back of his head.  "...Maybe a little," he admitted.

Mockingbird shook her head.  "Everyone's still adjusting to this place.  Couples are sticking together so far, and everyone we've met hasn't gone beyond flirting yet.  They're still uneasy," she said, sipping her wine.

"That makes sense," Mary Jane said, fiddling a little with the tight spandex that adorned her body.  She couldn't help feeling a little self-conscious around Mockingbird's toned, athletic form.  

Hawkeye chuckled, and leaned in to pat Spider-Man on the shoulders.  As he did, he discreetly slipped a card underneath Spider-Man's mask and quietly whispered, "Cap and Tony think something's up," he said, "and the others agree.  We've got an alliance with a group from another world called the Justice League that has the same reservations.  We're all playing along for now, but stay in touch on the communicard.  Let us know if you find something."  

Spider-Man just nodded, glad someone else felt something was weird.  Hawkeye, satisfied that Spider-Man understood, backed away, smiling.  Spider-Man discreetly slipped the card out of his mask and into his belt.  "Anyway," Hawkeye said, the archer pulling his mask down, "there's places like this all around.  Forests, mansions, temples, cities, basically any setting for sex you can imagine, all of them based on real places in the homeworlds of everyone who's here, this place warping you around at will.  You've obviously noticed that we're in an Avengers Mansion lookalike.  We're gonna explore right now, see if we can work our way up to actually having a good time with someone other than each other.  Not that we don't like doing each other, but it'd be a shame if we wasted this opportunity."  

Mockingbird nodded.  "Some of us may be further along the path to doing someone than others," she admitted, blushing.  

Hawkeye gave her an amused look.  "REALLY now," he said.

"I could have sworn I saw Captain Jack Sparrow over by the docks," Mockingbird said, grinning a little.  "I've always had a thing for Johnny Depp..." 

Mary Jane laughed.  "Really, what girl doesn't?" she said.

Hawkeye feigned dismay.  "GASP AND SHOCK!" he said, gesturing melodramatically.  "Our brides are leaving us for pirates with lethal halitosis!"

"Indeed!" Spider-Man said, joining in and hamming it up just as much.  "Come, brother Barton!  We must take our leave of these harridans lest they debauch themselves in front of us!"

Hawkeye blinked.  "Actually, that'd be kinda hot," he said.

"I agree," Spider-Man said, both he and Hawkeye looking at Mockingbird and Mary Jane expectantly.  

Blonde and redheaded traded bemused looks and let out an annoyed utterance of "Men!" before sauntering off, letting their husbands get a good view of their swaying asses as they left, heading out of the mansion for the port Mockingbird mentioned.  Both Hawkeye and Spider-Man broke down in snickering before heading in the other direction. 

Mockingbird chuckled, shaking her head.  "So what's your name, honey?" she asked.

"Mary Jane... Parker," she said.  "Spider-Man's my husband."  She decided to be honest, since the invitations promised renewed secrecy after everything was done.  Mockingbird nodded, remembering her modelling career.

"Kinda guessed that, since you were invited with him," Mockingbird said, giving her an appraising look.  "Parker... as in Peter Parker?  The guy who gets all those great Spider-Man shots?" 

Mary Jane nodded, grinning.  "Explains a lot, don't it?"  

Over with the guys, a similar conversation was happening.  "Yeah, yeah it does," Hawkeye said, laughing.  

"Well, I needed the money," Spider-Man said.  "Web-slinging doesn't really pay the bills.  Plus, I get a sadistic pleasure out of selling pictures of myself to JJJ, even if he does use them to villify me."  

Hawkeye shook his head.  "For such a nice guy, that's a really douchey thing to do," he said.

"Yeah, well," Spider-Man said, pulling off his mask, "Old brushstache brings it on himself a lot."  

Hawkeye nodded, smirking.  "True, true.  All the good he does and that damn mouth of his does him in every time," the archer said.  "He got dragged here too."  

Spider-Man paused.  "...So, what, prominent civilians were invited as well?"  

Hawkeye nodded.  "Everyone on the Helicarrier was invited, so the Helicarrier itself was pulled over to this place," he said, quietly adding.  "Last I saw it was heading south, towards the Castle Doom copy.  Last report there was that Doom was talking with a guy named Albert Wesker.  This Wesker guy had some kinda zombified monster with him."  

"Marvelous," Spider-Man muttered.  "Supervillains teaming up.  How're we supposed to enjoy ourselves here with the villains up to something?"  

They got their rather pleasant answer when they found themselves accidentally wandering out of the Mansion area and into an outside hot spring where several women were bathing.  The two men prepared to retreat, several of the women readying ki attacks, but they were talking down by the apparent leader of the group, who looked to be quite drunk and quite turned on by the two handsome men in spandex coming out of the nearby mansion...