There are multiple consequences. Firstly, his relationship with his father will be forever changed. He'll no longer be able to trust him in the same way. Secondly, his relationship with Ladybug might be affected. She may be more cautious around him, not knowing if he'll side with his father. Thirdly, Adrien will have to face the public's reaction if the truth ever gets out. He could become a target or be shunned. All of these aspects make for a very intense and emotional storyline in fanfiction.
He might be shocked at first. In many fanfictions, Adrien would feel a mix of disbelief, anger, and sadness. He has always known his father as a strict but loving parent, and finding out he's Hawk Moth, a supervillain, would completely shatter his view of him.
Because he wants to make his dad laugh. Simple as that.
Maybe Adrien says, 'Dad, why is Hawk Moth always so gloomy? Because he's in a bad'mood' (as in his evil plans).'
It could be Gabriel Agreste. He has been a suspect in the original series for various reasons. He is often absent and has a lot of secrets. So in the fanfiction, it would make sense if he was finally revealed as Hawk Moth.
Maybe the joke is 'Why is Hawkmoth always so stressed? Because he has too many akumas to manage!'.
One idea could be that his dad initially reacts with shock and disbelief. He might start to question how he didn't notice all the signs before. Then he could try to use Adrien's identity as Chat Noir to further his own business or social standing in some way, creating a lot of internal conflict for Adrien.
Common themes are transformation, not just in the sense of the Miraculous transformations but also in the characters' personalities. Hawk Moth might transform from a pure - evil figure to something more complex. Another is the exploration of the Miraculous powers. Fanfics often dig deeper into how the powers work and how they can be used in different ways against Hawk Moth. And secrecy is a big theme. Keeping identities secret, Hawk Moth's secrets, and how those secrets impact the story.
Well, perhaps Adrien has been reading a lot of cat - themed books or stories that are full of puns. He decides to tell his dad these puns to brighten his day. For example, he says 'Dad, I heard that cats are great at multi - tasking. They can nap and look cute at the same time!'. His dad might then join in and they could have a fun time coming up with their own cat puns.
One possible plotline could be that they initially struggle to adapt to each other's lives. Adrien, in his dad's body, might have to deal with the pressures of running a business, while his dad in Adrien's body has to handle school and social life. This could lead to a lot of comical misunderstandings.
A good fanfic about their bonding should have well - developed characters. The author needs to show the different sides of both Adrien and his dad. For example, Adrien's dad could be strict but also have a soft side when it comes to his son. It should also have a believable plot. Maybe something as simple as a day at the park where they have a meaningful conversation. The dialogue is key. It should feel natural, like a real father - son conversation.