Another theme is loyalty. Some fanfics might focus on Halibel's loyalty to her comrades or how that loyalty is tested in various scenarios. For example, if she has to choose between her old allies and a new cause. This can create a lot of drama and conflict in the story.
One common theme is power. Since Halibel is a powerful character, many fanfics explore her power further, like how she gains more power or how she uses it in different situations.
Identity is also a big theme. Halibel's identity as aArrancar and how that shapes her actions and decisions. Fanfics may explore her struggle with her identity, especially if she starts to question her place in the 'Bleach' universe or her relationship with other characters based on her identity.
Another theme could be the exploration of their different worlds. Ichigo is from the human world and Soul Society, while Halibel is from Hueco Mundo. Fanfictions might delve into how they bridge the gap between these two very different realms, perhaps through mutual understanding and cooperation. This can lead to interesting stories about cultural exchange in a sense, within the 'Bleach' universe.
There's also 'Halibel's New Path'. This fanfic focuses on Halibel's journey to find a new purpose outside of the conflicts she was previously involved in. It has some really interesting character development.
Another theme is the exploration of different worlds. The Naruto universe is very different from the Bleach universe. Fanfics often explore how characters react when they are exposed to the new environment, rules and cultures of the other universe. For instance, a Soul Reaper might be shocked by the idea of chakra in the Naruto world and try to understand it.
To develop their relationship, start with small interactions. For example, the OC could save Halibel from a surprise attack by other Hollows. This would make Halibel curious about the OC. Then, have them exchange stories about their lives. Halibel could talk about her rise to become an Espada and the OC could share their origin story. Another way is to give them a common goal, like protecting a group of innocent Hollows from a cruel Arrancar. Working together towards this goal would bring them closer.
Their powers could be combined in a way where Ichigo's Zanpakuto spirit, Zangetsu, and Halibel's water - based powers merge. For example, Ichigo could gain the ability to use water - enhanced slashes that have the cutting power of his normal attacks along with the fluidity of Halibel's water attacks.
Perhaps a plot where Ichigo accidentally ends up in Hueco Mundo near Halibel's territory. She initially sees him as a threat but then discovers that he has no intention of harming her or her fracciones. This could lead to an exploration of their different worlds and cultures within the Bleach universe.
One plot idea could be that Ichigo and Halibel are forced to team up against a new, powerful enemy that threatens both their worlds. They start off distrusting each other but gradually learn to respect and rely on one another's strengths.
Well, for a Bleach Halibel x OC fanfiction, a plot could revolve around the OC being a time - traveler. The OC travels back in time and meets a younger Halibel before she became an Espada. This could change the course of Halibel's life and their relationship. Or, the OC could be a musician in the human world whose music can reach the spiritual realms. Halibel hears this music and is drawn to the human world to find the source, which is the OC. Also, the OC could have a special ability to communicate with water, just like Halibel has an affinity with water - based attacks. They could bond over this shared connection.
One common theme is power. Yamamoto is extremely powerful, and fanfics often explore the extent of his power, like how he can handle really tough enemies. Another theme is leadership. As the head of the Gotei 13, his leadership style and decisions are often the focus. For example, how he manages to keep the Soul Society in order.
One common theme is the exploration of the power of Hyourinmaru. Writers often delve into how the sword's abilities can be developed or used in new and creative ways. Another theme is the relationship between the wielder of Hyourinmaru, usually Toshiro Hitsugaya, and the sword itself. It could be about their bond growing stronger or facing challenges that test their connection.