Maybe Harry acts all mysterious and brooding like a typical vampire. He might also wear dark clothes and avoid sunlight to convince others he's a vampire. Another possibility is that he pretends to have vampire powers like super speed or the ability to fly.
Well, you might want to check out 'Harry's Double Life'. In this fanfic, Harry pretends to be a Muggle exchange student to investigate some mysterious events at Hogwarts.
The Rani might raise Harry Potter by exposing him to rare and powerful magic, while also teaching him the importance of responsibility and caution.
In some fanfictions, the vampire inheritance might be triggered by a magical event. For example, a dark magic spell gone wrong or a curse placed on a family. This event could start the process of a character gradually developing vampiric features and powers. It could also be related to a specific magical object. If a character comes into contact with a cursed item, it could initiate the inheritance of vampiric qualities.
Well, in such fanfiction, it could be that Harry gains some extraordinary power or discovers a hidden magic that grants him immortality while everyone else around him fades away.
He could contribute great character designs. Gerard Way is known for his creative visual ideas. In vampire fanfiction, he could create vampires that are not just the typical pale, fanged creatures. He might give them unique appearances, like strange tattoos or markings that have significance in the vampire lore he creates.
It could be in a dramatic and public setting, like during a school assembly.
In some fanfictions, Harry Potter and Andromeda Tonks might discuss political matters related to wizarding society's governance and reforms.
In the 'Harry is a living vampire' fanfiction, Harry may display a range of characteristics. His immortality could be a major aspect, which would change his perspective on life and his relationships. He might develop a new set of moral dilemmas, especially when it comes to his vampiric needs. His relationship with magic could also be altered. Maybe his vampire nature gives him an edge in certain types of magic, or perhaps it conflicts with some traditional magic practices. His emotional state could be more complex as well, dealing with the isolation that often comes with being a vampire while still having his old connections to the wizarding world.
He might encounter rough seas. The boat could be hit by a storm, and Harry has to help the crew secure the sails and keep the boat afloat. This would be a real test of his courage and physical strength.
Well, regular Harry Potter fanfiction typically follows the events and rules of the original series more closely. But in Vampire Harry Potter slash fanfiction, Harry being a vampire brings in a whole new set of storylines. There are changes in his relationships. For instance, his friendships might be strained as he has to deal with his new vampiric nature. Also, the power dynamics shift. His magical abilities may be enhanced or altered in ways that are unique to the vampire concept, which is very different from the typical character development in regular fanfiction.