PLAGG IS ALLOWED TO SCREAM

                                    

                                          


                          
By the time both superheroes had turned eighteen and they still hadn't revealed their identities to each other, Plagg was very much done with the whole secret identities thing. If Adrien wasn't mooning over Ladybug then he was talking about Marinette, and if he wasn't talking about Marinette then he was plastered to the Ladyblog, going over the pictures of Ladybug to see if they could help him figure out Ladybug any better than he could while standing right next to the real thing during akuma attacks and planning meetings.
                          
The whole thing was wearing Plagg out. If Adrien could use his eyes (or his brain), then he might actually be able to figure things out. But Adrien was apparently blind (and Plagg had to admit, the Miraculous magic played a hand in that), and so Plagg had to listen to his Chosen yabbering on about the same girl literally all the time.
                          
(Even if he wasn't admitting it yet, Plagg knew that Adrien had a bit of a crush on his classmate. One simply could not spend so much time talking and thinking about one girl without being at least a little bit interested. Besides, Plagg spent all of his time with Adrien, and he had seen his Chosen's starry-eyed expression pointed in Marinette's direction before.)
                          
So Plagg decided to intervene, just a little bit.
                          
It wasn't Tikki- or Master Fu-approved, Plagg knew as he curled up with a chunk of lovely aged Camembert to brainstorm. But really, the big concern with sharing their secret identities when the two of them was younger was initially that one of the two might have to be swapped out. Then the concern was about how a reveal would affect their dynamic, because Chat Noir was ooey-gooey head-over-heels with his superhero partner and Marinette was tongue-tied around Adrien. But Marinette had long since managed to settle down and become proper friends with Adrien and Chat Noir had accepted his partner's gentle rejection several years prior. They were friends on both sides of the mask.
                          
There was no reason not to nudge things along a little bit, really. So Plagg wasn't going to feel bad about it at all. He couldn't outright tell Adrien- there were rules, and he wasn't able to just out and say it anyway, not unless he wanted bubbles to come out of his mouth instead- but he could hint.
                          
Heavily.
                          
Adrien was smart, Plagg told himself as he watched his Chosen work his way through his piles of homework. His grades attested to that, and he had gotten better at coming up with plans alongside Ladybug over the years of akuma fighting. If he dropped some really heavy-handed hints, Adrien would connect the dots and figure things out. With a little bit of nosing around, he would confirm his suspicions and then he and Ladybug could have a proper reveal and start dating and run off into the sunset with each other and Plagg wouldn't have to listen to Adrien's soppy sighing.
                          
He only hoped that it wouldn't take very long.
                          


                          
1. Coincidences
                          
Selflessness, kindness, and generosity aside, Miraculous holders tended to appear very, very similar to each other in the eyes of other people.
                          
Or at least they did when they had an enemy to fight and they had to slip away to deal with it, which Adrien and Marinette did. Classes had to be left, plans canceled, and excuses upon excuses made. It was frustrating to people they were close to, to be sure- Plagg had overheard more than a couple complaints from Nino and Alya when Adrien and Marinette showed up late to gathering or study sessions and then almost immediately had to run to the bathroom (for real, that time)- but necessary. They couldn't have civilians knowing their secret identities, even if said civilians were occasional superheroes (and yes, Plagg had figured that out pretty fast).