Sadia Al-Ghul Wayne, Alias Marinette Dupain-Cheng, was born to Talia Al-Ghul and Bruce Wayne.
Except Bruce doesn't know she exists.
Sadia chose not to meet her father after figuring out who he was. Instead, she did what any semi-sane person like her would've done-she ran away. She ended up in Paris, with Sabine Cheng and Tom Dupain. Being the awesome sibling she was (S̶h̶u̶t̶ ̶u̶p̶ ̶D̶a̶m̶i̶a̶n̶), She kept in contact with her twin. Now, they were going to the place her Father and Brother lived for a mandatory educational trip.
Fun.
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"Father, meet Marinette, Marinette this is Bruce Wayne, my father."
Bruce looked at Damian questioningly, but politely shook Marinette's hand. "Nice to meet you."
I quickly replied, "Likewise," And before Damian could say anything else, I added "I should probably be getting back now."
"Not so fast, Marinette" Damian said, grabbing my wrist.
That little-
"What." I hissed, glaring at him.
"Let's get to know each other better."
I elbow him. He deserved it, for being an ass.
"Wworth it." he said
"If you don't let me go, I'll be taking your arm as a souvenir." I whispered angrily.
"Still worth it." he said smirking- leaving me exasperated, his brothers shocked and Bruce confused.
(Credits to @Jinification for the cover- Thank you luv, it's the book cover of my dreams <3)