Chapter 1:

Today was Marinette's birthday. Adrien was not going to mess it up. He was not going to chicken out. He might throw up. Today he would tell her.

'Kid, just give her the freaking card'

'What if I'm wrong Plagg?'

'Then you need your eyes testing. You saw her transform back – before you say it, I know you didn't mean to – she's your Lady and your friend. Stop whining and bring me cheese.'

'What happened to "Your secret identity is super important"?'

'I miss Tikki.'

'Who?'

Just then Nathalie's voice called from behind his door, reminding him that he was going to be late if he kept watching TV (thank goodness the TV in his room could cover up his conversations with Plagg).

He tucked the enveloped card – and a disgruntled Plagg – into his bag and headed out of his room.

At school Marinette's desk was covered in birthday items. Alya had gone out early just to get her a foil helium balloon, and her classmates had all brought in cards or small gifts. Adrien smiled at how loved she was by her friends. Rightly so, he felt.

But the pile was also daunting, he really didn't want his card to get lost.

'Hey Alya, do you think Marinette would mind if I made sure I actually gave her the card from me?'

'She might burn herself up form blushing but I think you'd make her birthday!'

'Why would she blush, does she not like the attention? Maybe I shouldn't.'

'No no! No. You give it to her. She just… blushes when she's… Happy. I'll make sure you get some time to give it to her.'

True to her word, Alya made the time at the end of the day to force Adrien and Marinette together. By this point Adrien had talked himself out of giving to her, then back into it, then out again. Then Plagg had poked him with his claws and Adrien had finally determined that he definitely would give Marinette the card. Definitely. His hands clutched the envelope in a vain attempt to make them stop trembling.

Here she came. Oh God.

'My… Marinette! Hi! Birth Happy Day! Wait what?' he suddenly couldn't talk properly.

Marinette was blushing but also looking at him curiously. He was making an utter fool of himself.

'Thank you so much Adrien! Is… is that a card for me?'

'YEs!' he thrust the card at her with far more force than he'd intended. Holding his arm out straight and stiff.

Marinette gently plucked the card out of his grip. Her eyes shone with an emotion Adrien couldn't quite place, Alya really hadn't been kidding about how pleased she be about getting his card. Wait, she was actually opening his card. Fudge.

She pulled the card out. Little cat faces, in a variety of shades of pink and peach, stared back at her. In black text right in the middle read: "You're the cat's meow".

Adrien gazed at Marinette's face. No gasp escaped her lips, her eyes didn't widen in surprise. She just frowned slightly at the card in her hands. What if he had been wrong? Perhaps a doppleganger of Marinette Dupain-Cheng who also happened to be Ladybug was wondering the streets of Paris right now?

'It's purr-fect.'

Marinette's voice shocked him out of his panic. His eyes met hers.

'Really, I thought perhaps it would be paw-ful.'

Marinette beamed at him. Her grin cheeky and confident all in one go.

'Well, it wouldn't be very Lady-like of me to complain would it. To check though, you're not just kitten with me are you?'

'My Lady.' Adrien whispered. 'That's the most puns I've ever heard you make.'

'I'm older now, I appreciate more things.' She whispered back.

They had been edging closer to one another, when the Limo horn sounded making them both jump.

'I'll see you tonight? Please?' Marinette asked.

'You can count on it.'

Marinette and Adrien spent the evening really getting to know each other. Especially each other's lips.

Tikki and Plagg fell asleep curled up together for the first time in decades.

A/N:
This fic and the other chapters were inspired by the card shared by amazing and wonderful Tumblr user MiraculousLadyB, which can be found here: post/164720573841/i-found-a-card-that-chat-would-totally-get-ladybug