In some versions, it might end with Chat Noir realizing his mistake. He could come to his senses, either on his own or with the help of a friend. Then he releases Marinette and they work together to solve the real problem that led to the kidnapping in the first place.
The story could end with Marinette finding a way to break free from Chat Noir's captivity. She might use her wits or some hidden power she has. Once free, she confronts Chat Noir and they have a big fight that eventually leads to them understanding each other's perspectives better. And then they team up again to face the real threats in their world.
One possible plot reason could be that Chat Noir is being mind - controlled. Maybe an akuma - like force has taken over him and made him do things he wouldn't normally do, like kidnapping Marinette. Another reason could be a misunderstanding. He might think Marinette has some crucial information related to a villain's plan and he decides to take her to a'safe' place to question her. However, this is a very dark turn for his character.
First, you need to understand the characters well. Know their personalities, their likes and dislikes, and their goals. For example, Marinette is a creative and sometimes shy girl, while Chat Noir is flirty and confident. Then, create an interesting plot. It could start with a problem or a mystery that they need to solve together. Also, make sure to write good dialogue. Let their conversations show their relationship and feelings. For example, Chat Noir's flirty remarks to Marinette can add a lot of charm to the story.
Marinette would likely be very frightened at first. She might scream or try to fight back. After all, being kidnapped is a terrifying situation.
Another reaction could be that Marinette pretends to cooperate with Adrien at first. By doing this, she can buy time and look for an opportunity to escape or get help. She might act as if she is okay with what is happening while secretly planning her next move, like leaving a clue for someone to find her or finding a way to disable Adrien temporarily.
To write an engaging plot for this fanfiction, focus on the relationship between Chat Blanc and Marinette. Explore their past interactions and how this new situation changes everything. You could have Marinette using her wits to outsmart Chat Blanc. Maybe she discovers a weakness in his power or his state of mind. And don't forget about the setting. A dark, secluded place where she's held captive can add to the atmosphere and suspense of the story.
It could end with Lily escaping and being forever angry with Snape. She might cut all ties with him and go on to marry James Potter, with Snape left full of regret for his actions.
Often, it ends with Draco having a change of heart. He realizes the wrongness of his actions and releases Ginny. This could be due to seeing Ginny's vulnerability or her kindness towards him even in captivity. They might even become friends or something more in some cases. Another common ending is that Harry and his friends rescue Ginny. There's a big showdown where they outwit Draco and his accomplices and save Ginny.
Their relationship could become more strained. Chat Noir might be initially suspicious of Marinette having the Butterfly Miraculous, as it has been associated with Hawkmoth. He might worry that the power could corrupt her. For example, he could be on edge during their battles, constantly watching Marinette's actions more closely than before.
One interesting Chat Noir and Marinette fanfic could be 'The Hidden Bond'. In this fanfic, they discover a secret connection that dates back to an ancient magic. It's filled with adventure as they explore the origins of their powers together.
Well, in a fanfiction where Chat Blanc kidnaps Marinette, one possible outcome could be that Ladybug's friends come to her rescue. Maybe they discover Chat Blanc's hideout through some clever detective work. Another possibility is that Marinette manages to talk some sense into Chat Blanc, using her understanding of him from their previous interactions as Ladybug and Chat Noir.