Many 'little ichigo fanfiction' works have the theme of mystery. Given that Ichigo's father has secrets and the whole world of spirits is full of mysteries, when Ichigo is younger, he's starting to uncover these things. This can lead to exciting storylines where he's constantly learning new things about his family, his powers, and the hidden world around him. For example, he might start to suspect his father's true identity and embark on a little investigation of his own as a child, which makes for an engaging read.
One common theme is growth. Since Ichigo is depicted as little, his journey of becoming stronger and more aware of his powers is often explored. Another theme could be friendship, like how his relationships with his friends in Karakura Town develop at an earlier stage.
One common theme is the exploration of different worlds. Since Ichigo comes from a very different world compared to My Little Pony's Equestria, stories often focus on how he adapts and what he discovers in this new magical place.
A common theme is the exploration of their dual natures. Since Ichigo has his own powers and the female hollow ichigo has her unique hollow characteristics, fanfictions often play with how these two different yet connected aspects interact.
One common theme is the battle between good and evil within Ichigo. His normal self represents the good, while Dark Ichigo represents the more primal and sometimes malevolent side. Another theme is self - discovery. As Ichigo grapples with Dark Ichigo, he often discovers new aspects of his own power and personality.
Another theme is friendship. Given that both characters are known for their strong bonds with their friends in their original series, fanfictions like to explore how they would form a friendship with each other. They might start off as rivals and then grow to respect and trust one another over time.
There are also fanfictions that focus on the relationship between Hollow Ichigo and other characters. For instance, how he interacts with Rukia or Uryu. Some stories might explore if Hollow Ichigo can form alliances or if his presence affects the relationships Ichigo has with his friends. The exploration of Hollow Ichigo's backstory and origin can also be a theme in these fanfictions.
One common theme is the development of relationships. It shows how Ichigo forms bonds with the different characters in the harem.
One common theme is leadership. Since Ichigo is in a captain position, stories often focus on how he leads his team, makes tough decisions, and earns the respect of his subordinates.
Love is a very common theme. Often, there's a romantic relationship between Ichigo and a vampire character, which is full of passion and conflict. Another common theme is power. Ichigo's new - found vampire powers and how he uses or struggles with them is frequently explored.
One common theme is power combination. Since both Ichigo and Lucy have distinct powers, fanfictions often explore how their powers could work together, like Ichigo's sword skills combined with Lucy's celestial spirit magic.