(let's pretend Puppeteer 2 and Kwamibuster happened before Desperada, yeah?)
Adrien stifled his yawn as he walked through the school doors. He couldn't sleep at all last night, thanks to the unrelenting nightmares of yesterday's akuma attack. Battling Desperada was a harrowing experience - seeing his Lady, seeing Ladybug vanish before his eyes, in his arms... her shocked cries, her wide eyes, her vanishing form, and the devastating number 25,913 played on repeat in his mind. And the worst part about it was that some of those memories were attributed to his lack of focus on the job as he had prioritised flirting with Ladybug. He had been kicking himself since - how could he say he truly loved Ladybug, the one who entrusted him with her life, when he betrayed that trust for his own personal interests?
A yelp broke him out of his mental self-flagellation and drew his gaze to the middle of the courtyard. Some student had tripped and accidentally spilt the hot chocolate in their hand onto Marinette's shirt. Adrien was already making a beeline for Marinette before he even realised he had started to move. The student was apologising profusely to Marinette, who was trying to reassure them that it was an accident, suppressing her winces of pain the scalding beverage had caused. Adrien never ceased to be amazed by Marinette's strength and compassion, and his heart traitorously skipped - it had been doing that since the day at the wax museum.
'Hey, Marinette,' he greeted, wrapping an arm around her shoulder, 'let's get you checked out at the nurse's office.'
'A-A-Adrien! Hi!' she greeted. 'Um, sure! Let's go. See you later, Jean!'
The student responded, the now empty takeaway cup limp in his hand, but Adrien had already started guiding Marinette away to the nurse's office.
'Are you okay?' he asked.
'I'll be fine, Adrien,' she answered in that same placating tone she used to reassure Jean, but he wasn't convinced.
'Well, let's just get you checked out and make sure that's the case, yeah?' he replied, ushering her through the nurse's door.
The nurse assessed Marinette's stomach and proclaimed that she was lucky that she wasn't badly burnt by the hot liquid, but she still required a cold compress on her skin to soothe the sting. After ensuring Marinette was otherwise okay, the nurse said she needed to pop out and get some medical supplies, so she left the two of them to oversee the office while she was gone. Once the door shut behind the woman, Marinette looked down at her shirt with a huff.
'What's wrong?' Adrien asked.
'Oh, nothing,' Marinette said, fiddling with the end of her shirt. 'It's just that I am going to be stuck in a dirty shirt all day today - and it's not even my fault this time!' She let out a small chuckle. 'Oh well. It's nothing I haven't dealt with before.'
Her smile did nothing to alleviate the ache his heart felt. He knew his dear friend was a klutz, but it seemed that adorable trait of hers has made her suffer in ways he never contemplated.
'Let's switch shirts,' he blurted out. Her eyes widened.
'Wh-what?' she squeaked, her cheeks quickly flushing a pretty pink.
'Our shirts,' Adrien repeated, 'we should switch them - take my overshirt and use it in place of your t-shirt so you don't have to wear a dirty shirt all day.'
'Oh! That's very sweet of you! A-are you sure?'
'Definitely,' Adrien answered, removing his white overshirt and holding it out to her. She took it but didn't move to put it on, and instead stared at him awkwardly, her cheeks growing steadily redder by the second.
'Oh!' he exclaimed, quickly turning around to give her privacy to change. He ignored how his cheeks burned. 'Right, sorry.'
Aaand... he was standing in front of a mirror. Welp. He looked down at the floor, hoping that would work. He didn't want to be disrespectful, after all.
He accidentally looked up. Marinette had her back to him, in between changing shirts. Any other day and the sight would've made him blush, but not today. He accidentally looked up and saw what he shouldn't have and now he felt sick to his stomach.
'It's alright, Adrien, my skin stung, that's all. ...Adrien?' She turned around and met his gaze in the mirror. 'Adrien? What's wrong?'
She walked over to him, his shirt still in hand, her chest only clad with her bra, but that (unfortunately) wasn't what had gained his attention.
'Adrien, you're crying,' Marinette muttered, tenderly brushing a stray tear away with her thumb. Tender. Caring. Like she always was. His heart lurched.
'25,913,' he said, looking up and meeting her gaze. 'On your back - it says 25,913.'
She gasped, looking into the mirror to see for herself. She gasped again, her free hand covering her mouth in shock.
'I only know one person who could have a number like that,' Adrien continued, voice- well, everything shaking, really. 'And you're her.'
His knees gave way and he collapsed to the ground, Marinette barely catching him with a cry of his name. One of her hands wrapped around his back while the other cradled his face.
'Adrien, what are you saying?'
'You- you've been right here, with me, this entire time, haven't you?' he asked, his eyes desperately searching her face; all the pieces were falling rapidly into place now that he knew. 'I've been searching for you ever since I met you, and you've been here this whole time. I never thought- well, I did with Kwamibuster and you led me astray, but now- now...'
'Adrien, please, you're not making sense,' she implored. 'What's the matter?'
'I lost you. I lost you so many times, and I didn't think I'd lose you both! I- I... I couldn't lose you both, I just couldn't...'
He couldn't breathe. He couldn't see. Tears fell down his face so fast and he couldn't breathe and Marinette's arms wrapped around him and he clung on for dear life. 25,913. He lost her 25,913 times, and... and...
'I lost you, m'lady, and I lost you again and again and again and the Snake doesn't let you lose count- it doesn't, m'lady, it really doesn't and- and now- now you're Marinette, too - sweet, beautiful, kind Marinette - and I lost you both.'
'Adrien...' Marinette began hesitantly, 'why'd you call me that?'
'B-because that's who you are, m'lady,' he answered, burying his head into her neck. He felt her breath hitch.
'Only one person calls me that,' she said softly, 'and that's you, isn't it?'
He just held her tighter. Her skin was warm. She was alive. That awful, terrible number marred her skin and she was alive. Her skin...
He pulled away and picked up the shirt she dropped and draped the button-up around her shoulders.
'The nurse could walk in at any moment - we don't need anyone else figuring out your identity, Princess,' he choked out, holding the shirt in place as she slipped her arms through the sleeves. He started buttoning up the shirt with trembling hands. 'I can't lose you so quickly after finding you, I just can't.'
'And you won't,' she reassured, her steady hands holding his quivering ones. 'It's you and me against the world, remember?'
He couldn't help his quiver of a smile. 'As always, Marinette.'
hope this is something like what you were thinking of, Akari!