It could be a rogue Soul Reaper. Maybe someone who has turned against the Soul Society and sees Ichigo as a threat or a valuable asset. They might want to use his power to gain control over the Hollows or to overthrow the existing power structure in the Soul Society.
There could be a love story where Ichigo has a time - travel adventure and meets a version of Orihime from the past. This Orihime is different in some ways, yet still has the same kind heart. Ichigo has to keep his identity a secret at first, but as they interact more, he can't help but be drawn to her. She also feels a strange connection to this mysterious boy. As Ichigo tries to find his way back to his own time, he realizes that he has fallen in love with this different - yet - the - same Orihime, and the story becomes a race against time and his own heart.
Well, Ichigo could have a love story with Rukia. They have a very deep bond. Rukia is the one who first introduced Ichigo to the world of Soul Reapers. Their relationship is complex. There are moments of intense connection and understanding between them. They've fought side by side many times, and through these shared experiences, a form of love could develop. It might not be the typical romantic love at first, but it could grow into a deep and abiding love over time.
One possible plot could be that Ichigo is kidnapped by a powerful and unknown enemy. This enemy might be from a different realm or a secret organization within the Bleach universe. His friends then embark on a quest to find him. They might face various challenges and battles along the way as they try to track down Ichigo's location.
There could also be a powerful vampire hunter. This person might have a personal vendetta against vampires in general or specifically against Ichigo. They could use all kinds of weapons and tactics to try and kill him.
Well, a cool crossover fanfiction could be with the DC universe. Imagine Ichigo meeting Superman. They would surely have different views on justice. Superman is all about truth, justice, and the American way, while Ichigo is more about protecting his friends and the spirit world. Their meeting could lead to some intense debates and also team - ups against powerful villains.
One idea could be that Ichigo has to hide his vampire nature from his friends at first. He struggles with the new instincts and powers, like enhanced speed and strength. Maybe he has to resist the urge to drink blood from his loved ones.
Another great character to include would be Saitama from One - Punch Man. His nonchalant attitude towards fighting, despite being extremely powerful, would be really fun to pair with Ichigo. Ichigo might be frustrated by Saitama's lack of excitement during battles, while Saitama could be intrigued by Ichigo's complex powers.
I'm not sure of a specific title off - hand, but you can often find some really cool ones on fanfiction.net. Look for ones with high ratings and lots of reviews. Usually, the ones that combine Ichigo's sword - fighting skills with Harry's magic in creative ways are the most engaging.
When it comes to the more complex plot points, the interaction between Ichigo's Hollow side and the Dark Magic in the Harry Potter universe is very engaging. For example, if his Hollow side was somehow influenced by the Dark Arts or if it could be used to fight against it in a unique way. This could lead to a whole new set of challenges and character development for Ichigo within the wizarding world.