I'm not sure specifically as 'Bubbles got captive' could have various interpretations in a Powerpuff Girls (PPG) fanfic. It might involve a plot where Bubbles is captured by some villain or in a dangerous situation that the story then unfolds from.
It might be a powerful magical being. This being could be on a mission to study the Powerpuff Girls' powers and in the process of capturing Bubbles, realizes she has a very special personality. He is intrigued by her and as they interact more, love blossoms between them.
Well, perhaps Bubbles is captured by a new villain who has some strange powers. While captive, she starts to notice different aspects of this captor. Maybe he shows her a different view of the world. And as time passes, she begins to have feelings for him. It could be a story about seeing beyond the initial bad impression and finding love in an unexpected situation.
A fanfic could focus on Bubbles making new friends outside of her usual group. Maybe she meets an alien who is lost on Earth and she helps the alien find its way home while learning about different cultures in the process.
It could be a new villain who has a soft spot for Bubbles. Maybe he's a misunderstood bad guy who just wants some attention. He might see Bubbles as a symbol of purity and kindness that he lacks in his life, so he kidnaps her in a rather desperate attempt to be close to her.
In such a fanfic, perhaps Bubbles would initially be terrified when kidnapped. But as time goes by, she might discover some kindness in her captor. Their relationship could develop gradually. For example, the captor might show her a different side of the world she never knew. And Bubbles, being the sweet and innocent one among the Powerpuff Girls, could start to have feelings for this person who is different from the usual villains she faces. This would create a complex dynamic where she has to balance her new - found feelings with her loyalty to her sisters and the city they protect.
This kind of 'fanfic' is not acceptable. Fanfic should be based on positive, legal and ethical themes. The idea of a sex slave is a very dark and immoral concept that has no place in proper creative works.
Definitely not. Fanfic communities usually encourage creativity within the boundaries of legality and ethics. The idea of a sex slave is completely against these principles, so it would not be a common type of fanfic at all. In fact, if such a thing were to be found, it would likely be condemned by the fanfic community.
Well, without having read the 'ppg bubbles pregnant by him fanfic', it's difficult to say precisely. It could be a creative and perhaps a bit controversial take on the Powerpuff Girls universe. Maybe it involves some sort of alternate storyline where Bubbles' character is developed in a very different way than the normal cartoon, with this pregnancy plot being a central part of exploring new relationships and character growth. But this is all speculation.
Obviously, Bubbles is one of the main characters. And then there's the demon. There might also be other Powerpuff Girls like Blossom and Buttercup who could play supporting roles, either helping Bubbles deal with the demon or getting involved in the overall situation in some way.