Adrien is like the stupidest person on the planet.
Realize who Ladybug is
Understand that she's not perfect
Realize that he's the guy she loves
Understand that Marinette isn't just a friend
Realize why she acts like that
Understand that his puns are terrible
Understand that the library (Evillustrator) and, worse, A VASE (Guitar Villain) aren't good places for hiding during the transformation
All obvious things.
*I'm not a hater, don't get wrong ideas. It was just for fun. I know he's nice, generous, humble, patient, understanding and also a bit naive; while many other characters aren't like this. Just keep calm.*