Fan theory time...about Ladybug's identity
Marinette looks so happy when Cat Noir promises not to tell anyone her secret. She smiles a little at his endearment. It’s so cute.
But when she tells him it’s best no one knows, she doesn’t say it as a fact or even that she would never tell him. She just gets sad and looks away as if she’s ashamed.
My fan theory / now headcanon is that Marinette isn’t scared of people knowing her identity for simply knowing it. I think she’s scared of people knowing it’s her. Just plain, simply, easily embarressed Marinette that she’s afraid of people finding out.
She was happy with how sincere and exctied that Cat Noir wants to know who she is. But she’s afraid once he knows he’ll be disappointed? She’s happy and confident as Ladybug but doesn’t want anyone to find out that she’s really just nobody Marinette. She doesn’t want to let down even Cat Noir’s expectations of her, which she feels would fall short if he knew she was Marinette.
It’s that mental complex of secret identities and even just secrets in general. We all put up a face or persona we want others to percieve. I want my friends to think I’m witty, smart, and cool. All the time. Even though its exhausting to do so. It’s a great mental theme the show is keeping in mind to relate to real teens, and even real people. Everyone goes through this no matter what age they are. And I really applaud the writers, animators, creators, etc. if they really do have that as her mentality because that was well thought out as a minor but important character and animation tick to keep in mind.
Just my thoughts