I have Elvarya a prompt to write a frostiron fic about Loki being ticklish, and we later decided to give each other single-word prompts for us both to do. So this is my part. It's kind of crap and pretty short, but hopefully you'll find it enjoyable. Expect more prompts to come.
It had been an accident that he found out. Well, in his defense, Loki didn't exactly warn him, either, and it was his fault for asking for a favor in the first place. It had started when the god appeared in Tony's workshop, the Avengers mansion empty except for a certain metal suit-wearing hero, who had been busying himself with the creation of a new weapon to enhance his suit at the time.
"You know it's polite to knock." Tony called over his shoulder, recognizing the cracking of magic and the soft clicking of shoes. It always irked him that Loki managed to find a way around all of the security he had spent precious time creating, but never voiced his complaints. He knew it would only give the god something to gloat about.
"Ah, but that would take all the fun out of it." Loki grinned, hands clasped behind his back as he made his way over to the workbench. "Shall we get started, then?"
"I'm ready when you are, baby." That earned him a glare, but Tony decided to ignore it. "You'll have to get all that armor off before we can do anything, though."
Loki began to peel away the layers of his armor, dropping it carelessly at his feet. When he felt Tony's gaze on him he smirked. "I never knew you were so eager to see me undress, Mr. Stark."
"Oh, didn't you? Here I thought it was common knowledge." Tony shrugged, winding and unwinding the measuring tape around his fingers as we waited. Eventually Loki was left in only a pair of leather pants and an emerald green shirt, his beaten and worn armor sitting in a pile on the floor. "Alright, arms out. And for the love of god, don't try anything." Tony instructed, and he was almost surprised when the only response was a soft laugh before the god actually did as he was told. And here Tony thought that was impossible.
He started working quickly, measuring the length of his arms and legs first, then full body, taking notes on the paper that he and Loki had desinged his new set of armor on during his last visit. Tony sighed as he looped the measuring tape around Loki's waist. "You know, SHIELD would have my head for this if they found out I was making armor for the enemy."
"Do not forget the deal we made, Stark." Loki reminded him. "You are simply returning a favor. Surely your petty organization would understand repaying a debt."
Tony sighed, letting his fingers trace over Loki's hips as he went to write down the next few measurements. Something stopped him, however. Did Loki just… flinch? He brushed his fingers over the same spot once again, noticing the god's breath hitch as he tensed.
"Stark." He warned through clenched teeth.
At first he thought it was simply a sensitive area. However as he tested it once more, letting the tips of his fingers stay just a little longer, Tony realized something. "Oh my god."
"No. Whatever you're thinking, stop." Loki growled.
"You're ticklish!" Tony laughed, poking his sides and laughing as the god squirmed and yelped in his failed attempt to get out of Tony's grasp. Tony held him in place, testing wherever else he might be ticklish and laughing when he found another spot that made him jump.
"I said stop!" Loki yelled, and whether it was a reflex or on purpose or even both, Tony stumbled back as a fist landed right in his stomach.
He gasped, loosing his grip only to be slammed against the wall behind him. "Calm down, tiger." He grinned, attempting to find Loki's sides once again but he wasn't fast enough and instead found his hands held high above his head. "Oh what a pleasant turn of events. Loki, the God of Mischief, is ticklish. I mean can gods even be ticklish?"
Loki was fuming. His face was beat red and looked about ready to pop, his breath coming out in heavy puffs. "It would be in your best interest not to try something like that again, Stark."
"Oh relax, it was just a little harmless fun. Don't get your panties in a bunch." He didn't let go, however. In fact the grip around Tony's wrists only seemed to tighten. "I won't do it again."
Loki rolled his eyes.
"I promise!"
"Somehow that doesn't seem to comfort me at all." He sighed, releasing his hold to prop his hands against the wall, still effectively trapping Tony. "Do you have everything you need?"
"Yeah I should be good. You'll have your new armor all nice and shiny and waiting for you in a week or so." Tony said, carefully maneuvering his hands to wrap around the god's waist while doing his best not to accidentally tickle him again. "And then Fury will probably kill me in my sleep when he notices."
"I expect nothing but the best."
"Only for you." He hummed, cursing his shortness as he reached up to pull Loki's lips to his. While distracted, he prodded at Loki's sides once more.
Tony groaned as his head smacked against the wall behind him. "Your leader will not be the only one after you head, Stark." Loki growled, vanishing with his armor in a flash of green.
"Yeah, I deserved that." he sighed, calling to Jarvis to delete the security camera history before going to find some ice. He grinned, however, and contemplated all of the ways he could torment the god later on through a few simple jabs at his side. Yeah, the headache was totally worth it.