"Why do you run so much?" Adrien asked Marinette one day.

They had just finished a workout session and were sitting side by side on the ground, backs against the mirror. For the past few weeks, Adrien had noticed that Marinette spends more time at the treadmill running than any other kinds of workout.

Marinette looked at him worriedly. His green eyes were kind and comforting and familiar. Spending time together like this has made them grow closer together. They joked a lot, flirted occasionally, and shared deep stories about each other's lives. They had begun to understand each other in ways they never did before. But even though they had grown to become very good friends, they both couldn't help but feel that there was something about the other that was beyond their grasp.

And they were right.

Unfortunately, there wasn't anything either of them could do about it, because they couldn't very well share their biggest, miraculous secret.

And so, when Marinette finally answered, she spoke slowly, as though weighing her words before speaking them.

"I run a lot so that I can do this!" She finished the sentence by snatching Adrien's bottle from his hands and running away from him. Her laughter followed her trail like a shadow.

Adrien smirked as he got up to chase her. She was a fast runner, and he knew he could only catch her if he outsmarted her. Adrien took an alternative route around the gym so that he would end up in front of Marinette. She ran straight into him and he grabbed her tightly, holding her to him.

"Gotcha!" he exclaimed.

She laughed and tried to smack him away, but her arms were pinned to her sides as Adrien kept his arms around her. He laughed at her feeble attempt. It was so adorable that Adrien couldn't resist leaning down and giving Marinette an Eskimo kiss, nose brushing against nose. Staring down into her familiar blue eyes, he said breathlessly, "Not bad."

Marinette laughed again, quietly this time. "Not bad yourself."

A moment passed and Adrien's eyes widened as he suddenly realised what he did. He let go of Marinette slowly, so as to not startle or offend her. He shifted on his feet nervously. "Sorry. I don't know why I did that."

"It's alright," Marinette cleared her throat awkwardly and straightened her shirt. She handed Adrien the bottle and gave a small smile. She could feel her nervousness creeping in on her, thanks to the feeling of Adrien's warm body against hers. It comes back from time to time, the nervousness, even though she had long been able to deliver coherent sentences to the boy.

"Sorry about, you know, that. The bottle, I meant. And making you run. And I'm sorry because, well I… You see, the thing is, I can't give you an answer to your question. I mean. I guess maybe perhaps possibly I could come up with an excuse but then I'd be, uh, I would be lying, to you. And I don't want to. It's just… I can't tell you because it's something that's kind of… you know, personal. And it's not that I don't trust you! Because I do. Trust you. Of course! It's just…"

Adrien held his hand up to stop her. "I understand," he said sincerely. "There are just some things we can't tell anyone. We all have our secrets."

He winked and Marinette nodded, grateful that he didn't question her further. Adrien wondered what kind of secrets Marinette has, but he decided it was best not to pry. After all, curiosity killed the cat.

Chat Noir and Ladybug ran.

They occasionally looked at each other with deep frowns on their faces. Every time their eyes met, they would scowl.

They landed on the Eiffel Tower at the same time. Chat Noir crossed his arms as Ladybug walked angrily towards him.

"I got here first!" Ladybug yelled.

"No! I did!" Chat insisted. He was actually on the brink of laughter.

Ladybug groaned loudly in annoyance for all of Paris to hear. "Fine! Let's just be mature young adults and agree that we got here at the same time."

"That's no fun," he scoffed.

"This is the second time tonight we're competing. Both times ended with a tie! I'm not going to run again just to prove a point."

"C'mon, My Lady," Chat said, the fake frown dissipating from his face, replaced by his signature smirk. "Third time's the charm. Time to find out which one of us is really the fastest."

Ladybug crossed her arms and looked away. "Nope," she simply said.

"Come on. You afraid to lose?" Chat said challengingly. When she looked at him, there was a glint in her eyes and a grin on her face. Chat Noir almost laughed and beamed with self-pride – he knew his lady well.

"You asked for it," she said.

Ladybug reached behind Chat Noir to grab his stick, then took off, running and jumping from roof to roof. She caught Chat by surprise, but he recovered quickly and chased after her.

He knew she was fast, and they didn't have to compete for her to prove it. But Chat just loved the look on her face every time she tried to convince him she won, then exasperatedly gave up and decided that it was a tie. She looked so cute. And it really was a tie.

This time though, she got a head start. He decided the best way to catch her was to outsmart her. A while later, Ladybug saw Chat Noir running at her left, straight towards her. But as soon as she noticed him, it was too late, and they crashed into each other.

Chat kept his arms around Ladybug and tucked her head into his chest to protect her as they fell and rolled into a random rooftop. They came to a halt with Chat underneath Ladybug, a grin on his face as she propped herself up without getting off him.

"It's a tie," he told her.

"No, you won. You caught me."

There was something off in her voice, even though she said it with a smile, and it didn't go unnoticed by Chat Noir.

"Only because you took so many turns to try and throw me off. You were heading towards the school – I figured it out at your fifth turn. After that I just ran in a straight line and hoped that we somehow would end up colliding."

"Guess that makes you a really smart kitty."

"I am, thank you for noticing. But I must admit, it takes a lot to outsmart you," he said genuinely.

Ladybug smiled down at him and ruffled his already messy hair before getting off. There was an odd look on Ladybug's face as she tried to get up and leave.

Before she could, Chat grabbed her wrist gently and pulled her down again. They sat together, legs intertwined. Chat moved his grip to her hands, holding them tenderly.

"Ladybug," he began quietly, remembering the worries she had voiced out to him earlier in the day, "you didn't need to prove to me or yourself that you're a fast runner. You just saved a woman's life today! If you had gotten to her a second too late, she would have been pushed and she'd fall into the river.

"And that's just today. Every day you save people, and you always get there in the nick of time. You don't have to worry or think you're putting lives at risk because you aren't fast enough. Because, my lady, you're as fast as lightning. Metaphorically speaking."

She smiled at him and teared up at the words. He understood her so well, sometimes, even better than herself, and he always knew what to say or how to make her feel better.

Ladybug removed one of her hands from Chat's tender grip and placed it on his shoulder, squeezing it gently. She looked into his eyes and earnestly thanked him.

He half-joked that she should thank him with a hug.

Ladybug immediately complied.

When they had said their goodbyes and went separate ways, they each thought about their workout buddy. Marinette, confused over her ability to confide and find comfort in Chat Noir and not in her own crush. And Adrien, upset over his inability to help everyone around him but the one person he had started caring a lot about – Marinette.

They both decided that secrets truly were the hardest burden anyone had to carry. Especially when you don't have a choice.

Originally, I intended for 3 chapters and this was the ending I had planned out. Didn't expect such overwhelming support, so I ended up becoming dissatisfied with this ending. As such, this isn't the end of the story! I'll keep on posting several more chapters until it finally feels right to conclude. Thank you for all the support! :) I guess I'll see you soon :)