All Spidermans are 18+
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The tour of Stark Tower wasn't quite what Peter had expected. Not that he expected Willy Wonka-style shenanigans, but a few more gadgets and a lot less admin would be nice. Still, he was grateful for the armour Stark had given him so tried not to complain.
Thankfully Tony's attention span was equally short. "You look bored. Why don't I show you where I keep my toys?" he said with a twinkle in his eye.
Peter accepted excitedly! Stark led them to the elevator, input his personal code, and they began to descend through Stark Tower past hundreds of floors.
"It's in the basement?" asked Peter.
"More private down there. You're very lucky. Nobody else gets to see this part," said Stark.
"What about Mrs Potts?"
"Especially not Pepper."
The elevator came to a stop in a deep basement level. Peter was aware of the thick concrete up above, a sense of nervous claustrophobia tingling his senses. Nowhere to swing away here.
There were no people down here. But two synthetic figures strolled smoothly towards the elevator in response to its ding, their broad hips and full metal asses wiggling.
"Are those... Ultron?" Peter exclaimed, sinking into a defensive stance.
"He's been neutered, I can assure you," Stark grinned, sweeping the gynoids into his arms. "Hello, ladies." They cooed deep replies of 'hello, master', rubbing their sexdoll-shaped chassis against him.
"Is it safe keeping him around like that, Mister Stark?"
"Of course it is. Keep your friends close and your enemies closer. Much, much closer," Stark grinned.
Peter peeked into one of the side rooms. There was a jacuzi in one. "This place seems a little... seedy."
"What, Hugh Hefner gets a whole mansion. I can't have a single floor?" Stark scowled. "Ya gotta learn to unwind in this business, Peter."
"Would you like us to dispense lubricant, master?" asked one of the machines. The fact that Stark had kept the deep, gravelly voice creeped Peter out.
"Uhh, not right now," Stark said, shooing them away before wrapping his arm around his protege's shoulder. "Right now I've something very special to show you. Your upgraded suit."
It was tighter than his old one. Peter had to really squirm and wriggle to fit himself into the skin of blue and red spandex. And once it was on it pinched in all the wrong places. The inside was lined with metal ribs like a full-body corset.
"Go on, give it a try out. Walk around in it," Stark beamed, his eyes watching closely.
Peter walked to the far end of the room and back. He didn't know what Stark had made the suit out of it, but somehow it was very constricting, even to his enhanced muscles. He could catch 3000 lbs at 40 miles per hour, but managing anything more than a mincing wiggle in this thing was impossible.
The weight distribution was all wrong too. "There's a lot of, uh, armor on the chest, Mister Stark."
"Well that's where all the important organs are," Stark replied comfortably.
"And... uh, behind too?" Peter said nervous, cupping his plump cheeks. It didn't feel like armor, it felt like padding.
"The ass isn't an important organ too?" Stepping next to Peter, his fingers dug deep into the soft cushion of the buttocks. "I can add more if you like?"
Peter blushed. He didn't want to sound ungrateful. "N-no, it's fine, Mister Stark. I, uh, love it. The armors fine."
Stark smiled. "But you haven't seen the best part. I added a disguise function." He leaned close, moving his lips to the neck of the suit. "Form of: Romanov."
Immediately the thousands of metal ribs lining the inside of the suit articulated. They contracted like a vice around his waist, forcing his chest up and the air from his lungs. They expanded lower down, pushing him out until his shaped and shapely rear perfectly matched the hourglass figure of Black Widow.
A swarm of nanite liquid spilled out of the neck of the suit and up over Peter's jaw. He shut his eyes as the cold metal goo rolled up over his face. When he opened them again, there was long, crimson hair tight neatly on his head in a feminine style. He could taste lipstick on his lips, and his ears had been pierced, gemstone earrings now dangling from them.
"Holy shit," Peter gasped. There was a vibration from the neck of the suit as he smoke, the voice emerging from her lips perfectly mimicking Romanov's sultry purr.
"Indistinguishable," said Tony softly, his hands roving over Peter's new curves. "Did you know she was my assistant once? But she turned me down. The one who got away.... Perhaps there's still time for me to add her to my collection."