[Inertia]

Newton's first law of motion:

Sometimes referred to as the law of inertia. An object at rest stays and rest and an object in motion stays in motion with the same speed and in the same directionㅡunless acted upon by an unbalanced force.


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Never in his life had Adrien been so restless at his school desk. More than once Nino reached over to slap his pencil flat on the tabletop, whispering for him to cut out the incessant drumbeat he had been tapping since sitting down that morning. It wasn't his fault! How was he supposed to concentrate when he knew he would be seeing Ladybug later? He would be meeting her and she wouldn't be wearing her mask and he would have to control himself and not look and… ugh! He buried his head in his hands as the looming prospect of the 10pm meetup overwhelmed him once again, earning another confused glance from Nino.

Mme. Janvier may as well have been speaking Russian considering the amount of the lesson he was able to soak in. At the end of her lecture when she allowed everyone to pack up for the next period, he looked down at his notes and saw only nonsense, interspersed with doodles of cats and ladybugs.

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All day Tikki searched in vain for an opportunity to slip from Adrien's bag to Marinette's. Plagg lay back on Adrien's bunched up scarf, as amused by Tikki's determined station at the zipper as he was by the fact that Adrien's precious Ladybug was apparently within arm's reach of him during school hours. That tickled him to death.

"Gotta hand it to Fu," Plagg pointed out as Tikki shied away from the zipper yet again, chickening out on making a break for it as a student wandered up the aisle. "He really knows how to pick 'em."

"You know Fu doesn't pick them," Tikki reminded him. "He just finds them." She huffed, giving up for now and settling into the folds of the scarf with Plagg. "But honestly. This is the most dramatic irony we've had in ages. It's going to be so difficult to keep this from Marinette when I return to her. I hope this plan of Adrien's works, Plagg, because I hate leaving her defenseless like this."

Burrowing himself a little bit deeper into the glacier blue cashmere, Plagg closed his eyes. "Relax. Take a cat nap with me. It'll work."

"I don't know," she fretted, manually prying open one of Plagg's eyes. "Are you sure Adrien won't peek when she shows up?"

Plagg cackled at that. "Oh yeah, I'm sure. You really got him good yesterday, Tikki. You don't know him like I doㅡyou struck the fear in that poor sap's heart with that speech of yours. You realize he's in love with her, right? Like with the swooning and pining and poetry and everything. He wouldn't dream of putting his feelings above her safety. We are golden."

"Poor Adrien," Tikki pouted. From what she'd seen of him in person, he was all and more of the kind-hearted saint that Marinette had made him out to be. "This really isn't fair to them. You know, the only reason Marinette spurns Chat is because she's in love with civilian Adrien already!"

If that shocked Plagg he showed no sign. "Boo hoo. Other cats and bugs have had it worse."

"Sure, there have been greater hardships for previous holders, but never such an ironic romantic tragedy as this. You're so callous," she shot at him when he feigned a snore. "Don't you want Adrien to be happy?"

"Of course I do!" Plagg grumbled. "But you know how it goes, Tikki. Time and again, whenever we interfere it never helps. So we have to let all these complications run their course on their own. Let them chart their own path to equilibrium. The two of them are as complementary as you and I are, and the balance between them as delicate. We can't interrupt their journey (no matter how asinine it is) or the scales might tip off balance for good. They have to find it themselves, Tik. It's the only way."

In the dark of Adrien's bag, Tikki found herself sighing and slipping in closer, until she was close enough to press her head up against the god of destruction; her polar opposite in every way and yet her dearest, truest friend. "Oh, Plagg."

"What?" If kwamis could blush Plagg would have been glowing.

"I almost wish I didn't have to go back. I miss you so much when you're away." She felt Plagg lean in, ever so slightly, and she pulled the edges of the scarf around their shoulders to cocoon them together in the world's softest cashmere blanket. "You know that," she cooed, "don't you, chaton?"

A beat of warm silence, and then: "Yeah," he purred back. "I miss you too, bugaboo."

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By the end of the school day Adrien's nerves were in absolute tatters. Along with the jitters about meeting up with civilian Ladybug that evening, he'd become dangerously enamored with the idea of his lady beneath the mask turning out to be someone he knew. After all, Tikki had been on a first name basis with him, and had called it out only to immediately retract it. As if by knowing it she had dropped a precious clue.

A precious, tantalizing clue.

It could only mean one thing really, and that was that at some point, past or present, Adrien had made direct contact with the girl who was Ladybug. Maybe she worked with his father, or was a daughter of colleague. Maybe she went to school with him. Maybe she had simply met him on the street one day. Whatever the truth may be, it made him all the more desperate to know who she was. Being trapped in the dark this way had become nothing short of torture.

Only when his fellow students started filing past him toward the door did Adrien realize the school day had ended. As he started to pack up his things, Nino craned around in his chair to strike up a conversation with his long-time off-and-on sweetheart, Alya.

"By the way, thanks for the heads up yesterday, babe," Alya said. She tapped the bill of his cap with her phone affectionately.

"What do you think Ladybug lost?" he wondered.

"Not her miraculous?" Alya wondered with an edge to her voice. "You don't think?"

Adrien swiveled around to butt into the conversation. "I doubt it," he told Alya with confidence. "Not Ladybug. She's too responsible to part with her miraculous, willingly or accidentally."

"But I'm sure it's something important," Marinette added wistfully. "Uh, whatever it is."

Adrien nodded and she turned away, flushing like mad. "I'm sure. You think Ladybug saw the video?"

Nino laughed. "That video has gone absolutely viral; there's no way she hasn't seen it unless she lives under a rock. So what do you say?" He leaned on Alya's desk, wiggling his eyebrows up at her. "You guys wanna check it out?"

"Uh… what do you mean?" Adrien shifted his gaze from Nino to Alya, something about their gleeful expressions not quite clicking in his head.

"Duh!" Alya slapped both hands on the tabletop. "Everyone's going! We wanna see what Chat Noir's gonna give her!"

Adrien went white, and deep in his backpack Tikki and Plagg groaned in unison. Of course everyone wanted to know what precious possession of Ladybug's Chat Noir had found. Why hadn't he seen that coming? "Everyone's going, huh?" He tugged at his collar. How could he have been so naïve? (Marinette, meanwhile, was head-desking at lightspeed.) "Sorry," he weaseled, "can't make it. Piano recital."

"Boo," Alya pouted, and gave him two thumbs down, while Nino chimed in with a matching, "Laaame."

"Sorry guys," he shrugged. "You know how it is." No, he told himself, they don't know even half of the elaborate mess you're drowning in.

"But you two are coming, right?" Nino directed at the girls, and for the first time Adrien noticed how dejected Marinette was acting. Her cheek was pressed flat on her desk and she was staring straight out the window. Maybe they'd never grown too close (and maybe that was definitely his fault) but she was such a gentle, pure person that he felt a sharp tug in his heart when he caught sight of her tortured expression. Put simply, he cared about her. So he had to wonder what was wrong.

"Of course we are," Alya answered. "Wouldn't miss it for the world. Right, Marinette?"

"Right," Marinette answered without moving. "Uh…" She had noticed Adrien staring, and he flushed when she blinked down at him shyly. "Good luck tonight, Adrien."

Yeah, he would need all the luck in the world to pull off this crazy… wait, what? His eyes widened in panic. Marinette knew? She knew he was Chat and he'd be seeing Ladybug without her mask and he'd have to control himself and not look? She was so shrewd, how did she figureㅡ? Wait. No, wait. "Good luck with what?" he managed to choke out.

Marinette turned a deep shade of puce at Adrien's reaction, and he could see her second guessing her words. The more nervous she grew, the less nervous he became. "With your recital?" she squeaked.

Phew. She didn't know anything. She was just being Marinette (aka, incredibly nice, and damn he felt bad about lying when she wished him luck with such sincerity).

The blood rushed back into Adrien's head, making him dizzy. Why did he assume that? He must really be nervous. "Ha, of course. Thanks, Marinette, that's sweet of you. Oh no, I'm late for Mandarin!"

This was unfortunately true, and he leapt up out of his seat and bounded toward the door, dragging his bag along behind him, heart still pounding a million miles an hour. His friends watched him go with an air of confusion, wondering what on earth had gotten into him.

Out in the nearly empty hallway, Adrien gripped his bag tightly to his chest as he hustled toward the front doors. "This is a disaster," he whispered through clenched teeth.

"You still have to go," Tikki whispered back through the bag. "If she shows up and you don't, she might think something bad has happened to you, or to me. I know her. She'll panic."

"But how am I gonna know which one is Ladybug when everyone in Paris shows up?"

He wrinkled his nose at the sound of Plagg's uncontrollable laughter. "You won't! This is hilarious."

After a brief spout of rustling, Plagg fell silent with an ow. "What Plagg means," Tikki whispered again, "is that you won't. But, as long as you make an appearance, Ladybug will know you're trying. I'm sure she's worried sick about me, just like I am about her. We'll just have to try again with another plan after tonight. I was uncertain about the merit of this one anyway."

"Hey," Adrien protested weakly as he emerged out into the brilliant azure afternoon. "Not cool, Tikki…"

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"Showtime!" Alya triumphed, unplugging her fully charged phone from Marinette's computer to hold it aloft like an Olympic medal. Marinette followed her and Nino down the stairs with less than a quarter of their combined excitement.

"Have fun, you three!" Sabine called from the somewhere out of sight in the bakery kitchen.

"And remember, home by midnight!" Tom shouted after them from the front door as they skipped down the street.

Marinette trailed behind Nino and Alya on the sidewalk, letting them occupy themselves with speculation and small talk while her mind wandered. She watched as the barest tip of the moon began to peek out from behind a distant building, below Venus where it hung near the horizon. She'd had a lot to think about over the last twenty-four hours, and there were a lot of regrets swimming around at the bottom of her stomach. If she had just given into Chat's wishes a long time ago and confessed her identity then none of this would be happening. Tikki could be in her pocket right now, if only Chat knew that she was Marinette. He could have paid her a late night visit last night to return her lost kwami.

She blushed at the very thought. Okay, scratch that maybe.

Just as easily, he could have called her up to meet. They could have met on a street corner, in a library, at her front door… Anything was possible if they were both in civilian clothes, and had each other on speed dial.

Not for the first time, Marinette found herself wondering after Chat Noir's identity. Sure she'd always been the one to insist upon secrecy, but it didn't mean she'd never wondered. She wondered all the time! And the fact that she knew he was wondering about her at this very moment only served to fuel her curiosity. After all, would it really be so bad to know? Maybe Tikki had exaggerated the danger. At this moment, the possibility of sharing their secret lives was only giving her excitement and hope. Maybe it was time to give up the ghost.

When they arrived it was just after ten, and the snowy square was filled with people. Cameras flashed and voices turned into fog in the air and halfway up the front face of the historic cathedral, Marinette saw a dark figure huddled in the silver shadows, stark in contrast. A thrill of longing went through her. Tikki was right there.

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Far above, Adrien stood between two wide pillars, propping himself up forlornly on his baton. "How long do I have to stay, do you think?" he asked the red kwami that was nestled on his shoulder, mostly rhetorically. He pressed the cold end of the baton into his forehead. "Ladybug must think I'm such an idiot, broadcasting the meeting spot on public television like that."

Tikki only nudged herself further into his shoulder, rubbing her cheek along his jaw. "How else were you supposed to get her the message?" she reasoned. "Stop beating yourself up, Adrien."

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Down on the ground, Marinette once again let herself fall behind Nino and Alya. "You guys go in for the close-up," she told them. "I'll hang back for the wide shot, in case things get really good." She held up her own phone.

Nino threw one arm over Alya's shoulders and shot Marinette a delighted thumbs up. "Thinking like a true director. Awesome, Mar!"

Alya shrugged off Nino's arm with an amused smirk. "Come on, Spielberg, we gotta push to the front before too many people crowd the steps."

Marinette watched her friends disappear into the crowd with a pout slowly dominating her face. What the heck was she supposed to do? After some brief and turbulous deliberation, she turned tail and left the crowded square. She was going to have to lure Chat away from the Notre Dame if she even wanted a chance at speaking with him. So with a new gleam of determination in her eye, she crossed the Rue de Cloitre de Notre Dame, heading for the fire escape on the building across the road to the north, away from the neighboring Seins. By 10:20 she was three stories up the building across the way, about eye level with Chat. She could still see his dark figure lurking in the shadows on the ornate Cathedral exterior. Now to get his attention.

Pulling her phone back out of her pocket, she grinned to herself. She had promised Alya she would use it…

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By 10:30, Chat finally noticed someone flashing a light at him across the road. Seeing the obvious signal for his attention, and still not eager to delve into the growing crowd below, he gladly deposited Tikki onto the ledge to wait for him and slipped around the side of the Notre Dame unseen before pole-vaulting across the street. Sure, it was probably just a fan, but anything was better than agonizing over LB.

"Oh," he breathed as he landed deftly on the fire escape in front of the girl who had signalled him. "Marinette! H-hey. Hi."

He sheathed his baton at his lower back, anxiety suddenly gripping him in waves. Even though she'd mentioned she would be here during class, he honestly wasn't expecting to see or speak to her tonight, here, alone, and after his little slip-up in class earlier, he was more than a little nervous to chat with her as, uh… Chat. What could she possibly want?

"So you remember me, huh?" Marinette stowed her phone and leaned into the railing, eyeing him with a twinkle of suspicion. She bit her lip, hiding a giggle unsuccessfully. "You save so many people every day. I must be a real gem for you to remember my name."

Adrien awarded her shrewdness with a cool, haphazard smirk, but inside he was sweating bullets. Idiot, you're making it so obvious that you know her! Play it cool, Adrien, god!

"A knight always remembers a princess," he scoffed, poorly attempting to dial back on the familiarity. In the process he said it more genuinely than should have been possible, garnering an eye roll from Marinette in response. "So what are you doing up here, anyway?"

"Funny. I was gonna ask the same thing." Marinette walked two of her fingers along the railing, eyes on the crowd across the street. "You really think Ladybug's gonna show up here with a thousand people snapping pictures right below? Doesn't seem like her style."

Following her gaze, Chat sighed heavily. "No. She's not coming. I… shouldn't have posted that publicly. The thing is, Ladybug and I are out of contact. I urgently need to give her something but I've no clue how to find her, and I don't know how to set up a private meeting without being able to reach her."

"You know what you need," Marinette said as carefully and casually as possible, "is a place only the two of you would know."

"Huh?"

"You know," she pressed, "like a secret place. Post a message again, this time with a place only Ladybug would be able to find. That's how you get your secret meeting."

"Marinette!" She jumped as he took her face in his hands, smushing up her cheeks with loud, unbridled affection. "Why didn't I think of that? You're a genius!"

"I know," she blushed, barely intelligible through the cheek smushing.

"You're friends with AlyaㅡI mean, the girl who runs the Ladyblogㅡright?"

It was difficult to nod with him holding her face like that, but she managed it, somehow. "Yesh. She'sh my main lady."

Chat beamed down at her, vibrating in place with rekindled excitement. "Think you could give her a message for my main lady? The Ladyblog has a smaller audience than the news, so there's less a chance for the location to leak. Plus I know that LB checks it for akuma reports. Just have Alya post a message from Chat Noir, asking Ladybug to meet me on the roof of the tallest building on the street where we met, same time tomorrow. Could you do that for me?"

Again, Marinette struggled to nod through the intense bout of cheek-smushing that had yet to subside.

"Great!" he purred, and threw his arms around her shoulders, pulling her in close for a smothering hug. "Thank you so much, you have no idea how much you just helped me."

Marinette couldn't respond. She was too busy fighting a desperate internal battle, because at that moment every fiber of her being was screaming just bite the bullet and tell him already! You're so close! Tikki is probably in his pocket right now, inches from you! You're making this more difficult than it has to be! After a moment of this debate her cowardice gained the upperhand. She hugged him back, pressing her face to his chest so as not to tempt herself any further into saying anything she might regret. But in the end curiosity won out. She pulled back, just a bit, unable to look up into his eyes, instead staring out past the Notre Dame to the glittering black surface of the Seine.

"Chat, why do you remember me?"

It was a valid question. Regular girl Marinette Dupain-Cheng and hero boy Chat Noir had only met on a handful of occasions. Thrice during akuma attacks, and once on a hushed snowy night. She'd been sipping hot cocoa out on her balcony when he passed by, then came back, dropping deftly and soundlessly into the fresh snow beside her. They had shared the rest of her cup in amiable silence. Marinette had then spent the rest of the winter break wondering why Chat had seemed so comfortable on her private terrace, between her and her withered plants; like he'd been there before, or had always planned to come, or perhaps had always belonged.

But that night was a year ago already. There were other civilian girls that he'd saved ten times more frequently, and she was truly surprised that he remembered her with such clarity that he would instantly recognize her, even in the dark. It made her wonder.

On Adrien's part, her question struck him dumb. Why do you remember me? He'd never expected shy, soft-spoken Marinette to come right out and air the obvious mystery like that, and now what was he supposed to say? Because we're friends irl. He couldn't tell her that! So he opted for partial honesty. Half-truth.

"Because, princess. You just stand out."

Marinette flushed, suddenly aware that they were still standing with their arms wrapped around each other, the impromptu hug having evolved into something else entirely. Something dangerous. She tore her eyes from the glassy black river and was surprised to see how tense he had grown. He too was surprised by her sudden nerves, and in that moment, as they met each others' eyes, they had to ask themselves.

Does he know who I am?

Does she know who I am?

After a long, tense moment, they each privately concluded no.

The other couldn't possibly know (the alternative was too alarming to entertain) and they made their bashful excuses as they retreated from the embrace. But neither of them could help the belated question that sprung up later that night, Marinette cuddled on her chaise and Adrien poised beneath his window. They hadn't thought about it at the time, so concerned were they both that the other had begun to catch on. But now that they were alone it was all they could think.

Marinette rolled onto her back on the chaise, biting her tongue as she instinctively began to ask Tikki for advice. Tikki was still gone. Safe, but gone.

With Chat Noir.

If he doesn't suspect I'm Ladybug, what the heck was that intimate hug about? Hugging him wasn't wasn't weird for her because she knew Chat on that level. They were partners and friends and so much more than that, and she was used to his affection by now. But to Chat she should have been just another citizen. Marinette groaned into her pillow, thinking of the glint of recognition that always flashed in his eyes when Chat saw her as a civilian, before dulling into the usual. What did it mean?

Back at home, Adrien leaned his forehead on the middlemost pane of glass that separated his bedroom from the rest of Paris. Tikki and Plagg tried to rouse him from his thoughts but he only shook his head, his lips pressing into a taut line. Soon Plagg led Tikki away to some other nook or cranny, explaining that when Adrien got in one of his moods there was just no getting through. Better to wait it out.

The glass was like ice on his forehead and it helped him focus on the fresh curiosity he had unearthed. As much as it flustered him to admit it, Adrien knew that Marinette liked him, and had known it for a long time.

Liked Adrien, not… not Chat!

Huffing loudly, he rapped his head a few times on the glass, only stopping when Tikki grew concerned. He was just so surprised! If she didn't suspect that Chat was Adrien, then what was with that intense, loaded look they had shared when he hugged her?


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Author's notes:

Please note that the use of names (Adrien, Chat, Marinette, and Ladybug) in this fic is important and I've put a lot of thought into which is used where. Because his story is written in the third person omniscient, you're going to see the internal thoughts of many characters throughout. I've taken to using their names to help distinguish the current focus of narration, which tends to switch back and forth when they are sharing scenes together. Take, for instance, the above scene with Mari and Chat. Mari thinks of him as Chat, but Adrien just thinks of himself as Adrien. So whenever you see me call him Adrien when he's currently Chat, that's because you're seeing Adrien's perspective at that moment. If you see me call him Chat when he's dressed as Chat, you're seeing him from Marinette's perspective.

Same thing goes for scenes with Lady and Chat. If I invoke the name Marinette it's because these are Mari's thoughts, and vice versa with Adrien. If I invoke the name Ladybug, that's because these are Adrien's thoughts.

This will help, later on, when the relationship between the four corners of the love square gets muddled and confusing. Most scenes that include both of them will switch back and forth like this, so it was important to me to develop a system early on before it got chaotic. Just expect this and you won't be caught off guard by it.