Whew, it's been a while since I've written a fic for these two cuties!

Ever since he had met Plagg and started his life as a Miraculous Holder, Adrien Agreste hadn't been surprised by many things anymore. I mean, let's face it, if a cat-like creature called a 'Kwami' suddenly shows up in your room and tells you that you're destined to be a superhero, nothing can surprise you anymore.

Or so he thought. It just happened that there was someone who managed to surprise him time and time again.

And her name was Marinette Dupain-Cheng.

He'd always had a soft spot for the girl, don't ask him how or why, but he considered her his second real friend (losing only to Nino). That alone earned her a pretty high place in his heart, but then there was the other thing, and he believed it to be purely instinctual, but just the mere thought of her being in any type of harm made his heart pound and stomach churn. That's the feeling that confused him, since he didn't even feel that way with Ladybug! (Although that may be because he was well-aware that the masked girl could protect herself just fine)

But that's just it. Any person who would give Marinette no more than a sideways glance would consider her someone who needed to be protected- frail, even. She was just that kind-hearted and optimistic, and anyone with those qualities was bound to be either naive or too kind for their own good.

But Marinette would debunk that stereotype the second you even thought of her in that way.

She was stubborn, fierce, and stood for what she believed in. Not to mention that she was surprisingly strong and quick on her feet, too. In short, the entire opposite of what she appeared to be at first.

Take right now, for example. Adrien - and he was almost one hundred percent certain everyone else - was staring in complete and utter shock at what was happening right in front of his very eyes. The only one who didn't seem all that surprised was Alix, but that was just because she was enjoying this way too much to let her bewilderment overshadow it.

Even Alya- who claimed to know the aspiring designer inside and out -was staring at the two with surprise in her eyes. Even so, she still had the mind to whip out her phone and film this 'legendary' occurrence.

The whole classroom had been cleared for both Kim and Marinette; tables and chairs had been pushed all the way to the back of the room except for two of them, which had been centered in the middle of the class so that everyone could stand around them and watch clearly as the two classmates tried to one-up each other.

The arm-wrestle match hadn't been planned or anything, it just had been one of the spontaneous matches between Kim and Alix as usual. After their match, however, everyone had been surprised to see Marinette actually challenging Kim to go against her and see who was stronger, actually getting annoyed when he claimed he would go easy on her.

But now it had been made pretty clear that that was a terrible idea on Kim's part.

He was clearly struggling, and Adrien was certain that he spotted sweat droplets on the other boy's forehead.

Lê Chiến Kim was actually struggling to hold his own in an arm wrestling match.

Marinette was actually winning.

But that wasn't all, they had all seen Alix beat him in arm wrestling a couple of times before, so the fact that a girl was beating him wasn't that big of a deal to them; even if it was someone as unexpected as Marinette.

No, the surprising thing was the amount of effort she was putting into it- or, better yet, the lack of effort.

She was holding Kim's hand tightly in her own with ease, a soft smile on her lips as she just watched him struggle, her other hand supporting her head. Her smile wasn't mocking or anything, it wasn't even cocky, it just wasn't in her personality to taunt or humiliate her opponent like that.

No, her smile was the same kind and gentle smile that all of them knew and were accustomed to. Adrien tried not to think too much of the fact that it had his heart pounding in his chest.

Finally, after what seemed like forever, Marinette's smile turned soft. "Sorry, Kim," she said, her grin widening. "Looks like I won."

And with that, her grip on his hand tightened as she turned her wrist and slammed his hand down onto the table.

The class went silent, and it took a while before they managed to snap out of their shock.

Kim was the first one to react. He calmly got up from his chair and walked up to her with a proud and impressed smile on his face. "Nicely done, Mari!" He praised, head tilted down so he could properly look at her with his towering height. "Who'd have thought you'd be able to beat me? I'm impressed." He quickly slipped his arm around her shoulders and pulled her closer so he could ruffle her hair playfully, which had her struggling and protesting in his grip.

Meanwhile, the green-eyed model was still staring at the sweet and somewhat shy girl in complete awe.

It were moments like these that had Adrien questioning his sanity.

Note Number #1: Marinette Dupain-Cheng was extremely kind.

Note Number #2: Marinette Dupain-Cheng was brave.

Note Number #3: Marinette Dupain-Cheng was insanely strong for a girl her age and weight.

Note Number #4: Marinette Dupain-Cheng had very quick reflexes.

Note Number #5: Marinette Dupain-Cheng was a pro at gaming.

Note Number #6: Marinette Dupain-Cheng had the agility of a circus monkey.

Okay, yes, Adrien had resorted to taking mental notes of Marinette. In his defense, he had been completely unaware that he was doing it, and by the time he realized it; he was already down to four.

Gym class was one of the blond's favorite classes. It was the one time where he could just play and run around and actually have fun. The best part was that he didn't even have to be Chat Noir to do it. It was also the place where he could let his competitive spirit run free, and he'd taken note of the fact that his competitive side always happened to surface when they were playing in teams and a certain black haired girl with pigtails was in the opposite team.

And he was again taking notes of something Marinette-related. If he didn't watch himself, it was going to become a habit.

He was just glad that he wasn't actually writing them down. That was when he'd need to start worrying.

Surprisingly enough, gym was the only class where she was able to form a coherent sentence while in his presence. He guessed that her competitive side was big enough to rival his, since the normally stuttering and blushing girl would go as far as challenging and making bets with him whenever they were the two last standing- which seemed to happen a lot.

Adrien did feel a bit like he was cheating, since all his running around Paris as Chat Noir tended to enhance his physical attributes as himself too.

Still, he found himself not caring one bit whenever Marinette was the one standing across the room from him.

Huh, maybe he needed to make a list about himself too, since he kept learning new things about himself whenever the topic was either Marinette or Ladybug.

The moment Adrien had walked into the room, he felt himself getting excited when he spotted the monkey bars set up for them to swing on. He had half a mind to just run up and leap across them in a cat-like fashion, but that would both be too obvious and just plain embarrassing.

From the corner of his eye, he spotted flaming brown hair entering the room and he turned because whenever Alya got out of the changing room, Marinette was close by- and damn it, was he really paying that much attention to her?!

At this rate, he'd need counseling 'cause this was turning obsessive.

Another thing to add to Adrien's list of weird characteristics.

In the middle of the girls' conversation, Marinette looked up and her eyes lit up when she spotted the monkey bars, her smile almost brightening the room and Adrien was almost sure that he was blushing. He couldn't help it, the look on her face was simply adorable.

Seriously, this was becoming worrying. At this rate, he'd forget all about Ladybug since his focus was entirely on Marinette. Still, he didn't feel as panicked as he should have been, and that little detail alone should've already told him enough.

From the way his blush darkened, he knew damn well just what was going on.

He got snapped out of his thoughts when the teacher called for his attention. "Adrien! Marinette! You're up!"

He blinked and looked up to see Juleka and Sabrina walking back to the bench, the purple-haired girl quick to pull her fingerless gloves back over her hands after having to take them off for the monkey bars.

The task was simple, swing across the bars as fast as you could and try to get there before the other had. To put it simply, it was a race on monkey bars.

The two of them walked up to the bars, both teens having a good mood about this particular assignment. Adrien glanced beside him and shot the girl a smile. "Ready?"

Surprisingly enough, she met his stare head on with a smirk. "Think you can keep up?"

Her words just prompted a smirk of his own and he was sure that his green eyes were shining with cat-like mischief. "Oh, we'll see about that, P-" He stopped there, dangerously close to saying Princess and it occurred to him that it was just way too easy to slip into his Chat Noir persona without even being aware of it.

Seriously, he was taking mental notes of all the peculiar qualities of a certain interesting girl, but failed to make note of the important things that could protect his identity.

After this, he was so writing everything down to clear his head.

The teacher gave the signal, and the two of them simultaneously jumped onto the bars, swinging across with speed that had their classmates blinking twice and rubbing their eyes to make sure that they were seeing it right.

Adrien, however, was feeling a bit troubled.

All this - swinging and laughing, even making bets with Marinette - it all felt so familiar. The sense of déjà vu being enough for his concentration to slip and one of his hands to accidentally let go of the bars. He was quick to grab hold again, but that short moment of hesitation was enough for Marinette to get ahead of him, reaching the end quickly and jumping off with a small flip, her agile and graceful movements doing nothing but worsening his déjà vu to the point where it was becoming maddening because he couldn't figure it out.

He landed beside her just seconds after, using the same technique as her, but whereas hers was more graceful, his was a lot more carefree and playful.

She smirked up at him playfully. "Looks like I won after all, K-" She stopped, her pretty sky blue eyes going completely blank as whatever she was just about to say seemed to shock her into silence. Her eyes locked on him, narrowing for a second before she shook her head and her eyes cleared up again. Whatever she just had been thinking was just too ridiculous to be true, either way, Adrien could clearly see that it must've been a worrying thought for her to slip into silence like that.

His mind flashed back to how easy it was for him to slip into his Chat Noir persona when talking to her, and he wondered if she had picked up on it too.

Damn it, he knew that visiting her sometimes as Chat Noir was a bad idea.

"Congrats!" He smiled, figuring that changing the topic was his best option at the moment, and he made sure to get rid of any trace of Chat this time as he talked. "Maybe I'll be the one to beat you next time."

His voice had turned playful again at the end, and Adrien realized just how little self-control he had when around her.

It seemed to work though, since she looked up at him with a smile that equaled his as she responded. "We'll see about that."

Note Number #7: Marinette Dupain-Cheng was a very competitive person.

Her smile turned soft, and Adrien found his heart skipping a beat, and he regrettably had to add another note to his list.

Note Number #8: Adrien Agreste was completely and utterly screwed because he had fallen hard for Marinette Dupain-Cheng.