A plot could involve a prophecy that mentions both Harry Potter and Seras Victoria. They have to find each other across their different worlds to fulfill the prophecy and save both the wizarding world and the world Seras comes from. Along the way, they face many challenges like different forms of magic that oppose them and the prejudices of the people in each world towards the other.
One idea could be a crossover where Seras Victoria somehow ends up in the wizarding world of Harry Potter. Maybe she is mistaken for a new kind of magical creature. Another could be a story where a wizard from the Harry Potter universe discovers the existence of Seras and tries to learn from her vampiric powers. A third idea might be a story set in an alternate universe where the magic of Harry Potter and the vampiric nature of Seras Victoria are combined to fight a common, powerful enemy.
In a fanfiction, their interaction could be really exciting. Seras Victoria is a strong and often silent character. When she meets Harry, who is a natural leader, there could be some friction at first. But as they face common enemies, like a group of dark wizards who are trying to use vampire blood for dark magic, they learn to rely on each other. Harry could use his magic to protect Seras from anti - vampire spells, and Seras could use her physical strength and vampire senses to help Harry in battles.
To start writing this fanfiction, begin by choosing a theme. For example, if it's about friendship, think about how characters from both universes can form bonds. Next, think about the setting. Will it be mostly in Hogwarts or in the world where Seras Victoria exists? You also need to consider the tone of your story. Is it going to be a light - hearted comedy or a dark, action - packed thriller? Once you've decided on these aspects, you can start outlining the main events of the story, such as how the two different worlds collide and the consequences of that collision.
One plot idea could be Alucard and Seras going on a mission together in a modern city filled with new types of supernatural threats. They have to use their combined powers to take down an ancient evil that has been awakened. Another could be a story where Seras struggles with her human emotions while Alucard tries to teach her how to better control her vampiric nature. It could also be interesting to see a story where they are transported to an alternate universe and have to find their way back while facing different versions of themselves.
Another plot could be about how their relationship changes during the pregnancy. Seras might become more vulnerable and rely on Alucard more, while Alucard has to learn to be more gentle and caring. For example, he might start to show a side of himself that he has kept hidden for a long time.
One interesting Victoria fanfiction could be one where Victoria is a new student at Hogwarts and she befriends Harry and his friends. She might have a special power that helps them in their adventures against Voldemort.
A possible plot could involve Schrodinger being sent on a mission with Seras by the Hellsing Organization. During the mission, they face a powerful enemy that forces them to rely on each other's unique abilities. As they work together, a deeper understanding and an unexpected bond form between them. This could explore how their different natures, Schrodinger's quantum - like existence and Seras' vampiric nature, interact and complement each other in the face of danger.
One interesting plot idea could be a story where Seras and Integra have to team up against a new and powerful vampire threat. They start to understand each other on a deeper level during their battles and form a stronger bond.
A different plot could be that a curse has been placed on both Naruto and Seras. They start having visions of each other's past traumas. As they try to figure out how to break the curse, they discover that it was placed by an old enemy of both the ninja clans and the Hellsing organization. To break it, they need to find a magical artifact hidden in a dangerous dimension that is guarded by powerful demons and rogue ninjas.
One idea could be exploring her early days as queen and her relationships with her advisors. Maybe a story where she has to prove herself to the older, more experienced men in her court.