In a fanfic, the Bulma - Chichi fusion could be part of a tournament arc. They enter the tournament fused and shock everyone with their abilities. Their opponents underestimate them at first, thinking it's some kind of strange trick. But as the battles progress, they show that their fusion is not only powerful but also has a deep understanding of both martial arts and strategic thinking.
Well, if they fuse, the new character would likely have Bulma's inquisitive nature. They would be constantly curious about new things, especially in the realm of science and technology. At the same time, they would also possess Chichi's determination. So when facing challenges, they would be very persistent.
Well, the plot could involve them fusing due to some kind of magical or technological accident. Maybe they are trying to defeat a powerful enemy together and their combined energy causes them to fuse. They could then have a new form with combined powers and a unique personality that is a blend of their own.
One possible plot could be that Bulma and Chichi team up for a scientific - martial arts tournament. Bulma uses her intelligence to create unique gadgets for Chichi to use in the combat part of the tournament. This brings them closer as they train together and face various opponents.
It could also be due to the way the fanfic writers handle their characters. If they write Bulma as a prideful character and Chichi as someone who challenges that pride, either directly or indirectly, Bulma might be written as hating Chichi. Fanfic often takes creative liberties and this could be one of the results.
One common theme is friendship. Since they are both important female characters in the Dragon Ball universe, fanfics often explore how they become friends and support each other. For example, they might team up to deal with some threats in the story.
One possible motive could be that Bulma is worried about Goku's safety. Since he's constantly getting into dangerous battles, she might think that if he's not tied down to Chi - Chi, he could be more focused on self - preservation. Maybe she feels that Chi - Chi's family demands on Goku are a distraction and could lead to his downfall in a fight.
Well, it could be about Gumball and Chichi going on an adventure together in a magical world. Maybe they discover a hidden land full of strange creatures and have to work together to find their way back home.
Maybe it could be about Chichi discovering her latent Saiyan powers. For example, she might start to have sudden bursts of energy during a fight or a training session. Then she has to learn to control these new powers, which could lead to her training with Goku or other Saiyan characters.
The plot might involve Bulma creating a new device that has some unexpected side effects. Gohan then comes to help her fix it. Along the way, they might encounter some old enemies or new threats. And perhaps through this experience, they develop a deeper understanding and friendship. For example, Bulma could be working on a time - travel device and accidentally sends them both to a different era, where they have to rely on each other to get back home.
It could be Frieza. He might be interested in Bulma's technology for his own evil purposes and sees Chichi as a threat because of her connection to the powerful Z - Fighters. So he tries to stop their partnership and steal Bulma's inventions.