Disclaimer: Neither Miraculous Ladybug, nor this idea are mine. I believe this one-shot was inspired by a tumblr prompt, please feel free to correct me if I am mistaken.

AN: I do watch the French with English subs instead of the English version of this show, as such, some of my terms are a little off (transform me, I'm freeing you from evil, etc.) but others do match the English, (Hawkmoth, alley cat, etc.)

Marinette had been idly browsing the fabric when she saw it. Polka-dotted fabric that matched her suit perfectly. She knew she shouldn't, having a costume just like Ladybug's? That was just asking for an accidental identity reveal. But the designer in her was immediately intrigued by the challenge. Could she make a suit like her suit? Seamless and covering all of her limbs? And the fabric was perfect. It was flexible enough that it really could make a suit, and thick enough that she wouldn't have to worry about underwear lines and the like… So she bought yards of the stuff, and yes, she did know exactly what she was doing, thank you inner voice that sounded just like Tik- Oh wait, that was Tikki.

MLMLMLML

"What do you think?" Marinette twirled in front of her mirror. It had taken her months, especially since she could only work in secret, but she had finally gotten the suit just right. The seams were all but invisible, and it fit her like a glove!

"I still think it's dangerous, Marinette!" Tikki hovered nervously near her head, "What if someone sees you?"

"Then they won't be able to tell the difference between me and Ladybug," Marinette said firmly, "Not with these,"

And with that, she added her final touches, She had sewn a small velcro patch onto her hip where her yoyo sat, and there she attached a replica, a replica that Tikki had been even more firmly against than the costume itself, until Marinette had modified it to contain cookies in a bribe. Then she picked up the mask she had worked so hard to make and undid her pigtails. She pulled on the mask and pulled the top half of her hair out from under the strap she had made of fishing line. When she redid her pigtails, it concealed the thin strap perfectly!

Suddenly, she heard screams from outside, when she darted to look there was… A half-lady-half-spider spinning a web on the eiffel tower. Of all things.

"Really? Now?" Marinette asked, and went to go towards the akuma.

Just as she was about to, Tikki shrieked, "Marinette! Wait! You're not actually Ladybug yet!"

Marinette stopped sheepishly, "Oh, right. Sorry. Tikki, transform me!"

And she transformed, and went off to save the day again. This time actually in costume.

MLMLMLML

Ok, so it was a bad day. Marinette had already used her Lucky Charm, a toothbrush of all things, though she did know how to use it, of course she did, if she could get it between the spider's pincers, then they could get at the purple headband that was so out of place, it had to be concealing the akuma, but it had been knocked out of her hand before she could get it there. And if that weren't enough, she and Chat were tied together with spider silk, which didn't even make sense, because this akuma was even more incoherent than usual, and she hadn't been able to make out much, but what she had been able to make out was something about shoes and what did spiders even have to do with shoes anyways? And Chat wouldn't use Cataclysm, because he was worried it might hit her, and that was ridiculous, except maybe it wasn't, because he was facing her, and ok, his hands were kind of tied to her sides, but she was stressed because her earrings were beeping and she literally had seconds before she de-transformed, and what the heck was she going to do?

"My lady?" Chat asked hesitantly, "I can hide my face if you want?"

"How?" she managed to get out, because that was even worse because Chat was always trying to figure out who she was, but he respected her enough to ignore the answer right in front of him and she had to admit that if the situation was reversed, she didn't even know if she could make the same offer, and wasn't that crazy, because she was the one who insisted on the secrecy, and Chat was so hesitant, and that wasn't like him at all, and he wasn't even making puns, and-

Chat's response cut off her frantic train of thought, "I can bury my head in your shoulder." He demonstrated and she could feel his breath against her neck and the pressure of his head on her shoulder, before it was gone as he raised his head again.

"I-" She paused because she wasn't sure and part of her was so grateful for this out he was giving her, but the other part of her thought that maybe it was for the best if he found out once and for all, and what did it even matter more, because that last beep had caught the akuma's attention and apparently Hawkmoth's too, because there was a purple-pink butterfly around the akuma's eyes, and she knew what that meant, Hawkmoth was watching, and she didn't know.

And suddenly she didn't have a choice anymore because she was turning back into Marinette now and her eyes blinked against the pink-colored flash like they always do, but it wasn't like always because she could still feel Chat's arms trapped against her waist, and-

"My lady?" Chat's voice was confused, and of course it was because she could see Tikki resting on the rope in front of her, and she was just herself again, and he was disappointed, of course he was disappointed, and- "How are you still in costume?"

"What?" she started, but then she remembered, she had made that stupid fake one, and suddenly, it didn't seem nearly so stupid, but they were still trapped, and now she didn't even have her powers and Tikki needed sweets, and- of course!

"Chat, can you reach my yoyo?" she asked excitedly, as she side-eyed spider girl, who seemed to have shaken off Hawkmoth's hold with the shock and was back to web-spinning.

"Uh, I don't know, I can try, but, what- how are you- why are you- you just de-transformed!" Chat spluttered.

"That's not important right now, Chat, it's just dumb luck, but can you get at it?"

"I'm trying," and sure enough, his hand was sliding down her side, and he was almost, almost, he had it!

"Ok, I've got it, should I pull it off?" he asked.

"No!" she shouted, "Don't!" it was just velcro, pulling at all would make it come off entirely, "Just twist it, clockwise, the top should could come off, and there'll be cookies inside,"

"Cookies?" Chat asked bemusedly, "Why cookies?" but she could feel him twisting the false cover away.

"For, Tikki, my kwami," Marinette explained.

"Your kwami eats cookies?" Chat asked jealously, "Plagg won't touch anything but camembert!"

"Wha-" And despite the seriousness of the situation, she choked on her laughter, "Camembert? Seriously?"

"Yes, seriously! And I'm sick and tired of smelling like cheese! Cookies of all things, those are delicious! How is that fair?" But he was working the cookie out of the container, and he had it in his hand, "Now what?"

"Tikki, ideas?"

The little kwami looked up, "Drop it, if I slide off the rope, I'll catch it in midair," and proceeded to roll over, and Chat did drop the cookie, despite Marinette's squawk of protest, because what if Tikki missed, but after a moment, she was fluttering in front of Marinette's face again, carrying the toothbrush!

But wait, "Chat, what are you doing with that yoyo cover?"

"Just a second longer, milady," he was wiggling it, and now it was between her and his hand, "Aha! Purr-fect! I can use my claws without scratching you, and cut us out of this rope," and his hand was rotating, and there hadn't been enough room in the rope already, that was making it worse, and wait- she was a civilian again, she'd fall to the ground if he cut them out now,

"Chat wait! Tikki, put the toothbrush in my mouth real quick?" Tikki gave her a weird look and complied, but it did make sense, she'd still need the toothbrush once she was Ladybug again, and Tikki wouldn't be able to hold it once in her earrings, "Tikki, transform me!" she mumbled around the brush.

She'd never tried to transform tied up before, and it was really awkward, but it got done, "Ok, go for it, Chat,"

And his claws had sliced through the rope and they were falling, but Chat's tail got a beam on the tower, and she had her yoyo out and doing the same in no time. She glanced around and saw what she needed light up as always, spider girl's mistake was following a predictable path, "Chat! That bolt, right there," and she marked it by hitting it with a pebble.

"Meow-nificent aim, milady!" He called as his staff propelled him to the spot, "Cataclysm!" and the bolt was gone, and the beam was loose, and if she just timed it- Now! Her yoyo shot out, and the beam was knocked out of place, and pinned one of the akuma's legs. She swung down and landed on the akuma's head and slot the toothbrush into place so that she didn't have to worry about falling into those pincers, and snatched the headband off of the spider's head. She broke the charm and yelled "I'm freeing you from evil!" and purified the akuma, "Bye-bye, little butterfly,"

She through her toothbrush into the air and watched as the damage reset itself and Chat swung down as the spider turned back into a girl. They traded their customary fist bump, and Chat asked, "Now will you explain how you de-transformed but stayed Ladybug?"

"Like I said earlier, Chaton, just dumb luck, it won't be happening again," she explained. And it really was dumb luck, and it wouldn't be happening again, because Marinette was going to take this costume apart as soon as she got home, she proved she could do it, and it payed off once, but she was just forcibly reminded of the importance of keeping identities secret, and this fake costume would be tempting fate.

"Yes," Chat said frustratedly, "but how?"

"Aw, didn't you know Alley Cat?" Marinette asked with a giggle, "Curiosity killed the cat!"

And with that last remark, she swung away. And Tikki couldn't respond right now, but Marinette knew she could hear, so she muttered, "See, Tikki?" on her way back home.

Please, let me know what you thought!