Definitely Hermione. She is smart and would be able to help Ichigo understand the complex magic world. Also, Hagrid. He is kind - hearted and has a lot of knowledge about magical creatures, which could be useful for Ichigo.
One possible plot is that Ichigo is reborn as Harry Potter's long - lost twin. He would then have to deal with the same kind of prophecy and the threat of Voldemort. But being Ichigo, he would approach things in his own way. He might not rely so much on magic wands but use his own spiritual power which could be disguised as a new form of magic in Hogwarts. This would cause a stir among the professors and students alike.
Fem Ichigo could interact with the Harry Potter characters in a very unique way. Given her own background, she might approach them with a mix of admiration and her own sense of self - confidence. For instance, she might offer to train Harry and his friends in some form of combat, something that could be useful in their battles. She could also share stories from her own world, which would be really fascinating for the Hogwarts students. And in return, she would listen intently to their tales of magic and mystery at Hogwarts.
First, you need to understand the basic elements of both universes. Know the rules of the 'Bleach' world regarding Soul Reapers and Hollows, and also the magic system in Harry Potter. Then, think of a unique concept for your story. For example, what if Ichigo was a wizard in Hogwarts? Next, focus on character development. How would Ichigo and Rukia interact with the Potter characters? Finally, just start writing and let your creativity flow. Don't worry too much about making it perfect at first.
When writing a fem Harry Potter Ichigo fanfiction, it's important to blend the two worlds seamlessly. You could start by mapping out how the different power systems will work together. For example, how would Harry Potter's magic interact with Ichigo's Hollow powers? Develop the characters well, especially the fem Harry Potter. Give her unique traits that are both true to the original Harry Potter character and also influenced by the new situation of being in a crossover. And don't forget to have a strong plot that drives the story forward, perhaps a quest to save both worlds from a common threat.
One possible plotline could be that Ichigo somehow gets transported to the Harry Potter world. He might use his Soul Reaper powers to fight against the dark wizards. Maybe he helps Harry and his friends in a battle at Hogwarts by using his Zanpakuto skills.
The combination of two very different universes. Ichigo from Bleach is a very different character from those in Harry Potter. His unique powers and personality, when put in the context of the wizarding world, create a lot of interesting scenarios.
One great Ichigo Rukia Harry Potter fanfiction is 'The Crossover Chronicles'. It combines the unique powers and personalities of Ichigo and Rukia from 'Bleach' with the magical world of Harry Potter in a really engaging way. The author does a wonderful job of creating new adventures for the characters in Hogwarts, while still maintaining their original essence.
There's a fanfic called 'Fem Potter and the Soul Reaper'. It delves into a scenario where fem Harry Potter crosses paths with the concept of Soul Reapers from the Bleach universe. It's a great read as it weaves together the different magical systems of both franchises in a very engaging way. The character development of fem Harry Potter as she adapts to the new elements is really well - written.
Ichigo's character develops by first being confused and out of place. But as he learns about magic, he starts to adapt. His sense of justice from the Bleach world makes him stand up against the bullies at Hogwarts, like Draco Malfoy. He also learns to use his powers in a new context. For example, he might combine his Soul Reaper strength with magic spells to create unique combat techniques.