Another way would be to travel via the Floo Network to different unmonitored locations. But they'd have to be very careful as the Floo Network could be watched. They might also change their appearances using Polyjuice Potion to assume the identities of other wizards who are not on Voldemort's radar. They could then move more freely in wizarding areas without raising suspicion.
They could use disillusionment charms constantly to blend in with their surroundings. This would make it difficult for Voldemort's forces to spot them. Also, they might use the Marauder's Map if they manage to get hold of it. It would help them avoid any approaching Death Eaters or other threats.
They could use magic to disguise themselves. For example, Hermione is very skilled at the Polyjuice Potion, so they might use that to change their appearances. They would also need to be careful with their magic use to avoid detection by the Ministry's trace. Maybe they would use non - traceable magic like some ancient spells that are not well - known.
The remaining Death Eaters could be the antagonists. Even though Voldemort is gone, there could be some who still hold a grudge against Harry and want to finish what their master started. They might track Harry and Ginny down as they run away, creating dangerous situations for the couple.
One possible plot could be that they run away to escape some dark magic threat that Voldemort's remaining followers are planning. They might go into hiding in a remote wizarding village, where they have to learn to fend for themselves without the help of the Order of the Phoenix. Along the way, they could discover new magical abilities or ancient spells that help them in their fight against the dark forces.
Well, one possible plot could be that they run away to escape some sort of dark threat at Hogwarts. Maybe a new dark wizard has emerged and they feel that the school is no longer safe. So, they secretly gather some supplies, use magic to disguise their departure, and head off to a remote location like a hidden wizarding village in the mountains. There they try to find a way to fight the threat from afar while also exploring their relationship in a more private setting.
They might choose to run away secretly because they want to be alone together. They are in love, and the hustle and bustle of Hogwarts life doesn't give them enough privacy. So, they run away to a quiet place where they can enjoy each other's company without any interruptions.
One reason could be to escape the constant media attention and pressure that comes with being in the wizarding world's spotlight. Harry especially has always had the eyes of the public on him, and running away might be a way to get some peace.
One reason could be to escape the public spotlight. After the war, Harry is a hero and Ginny is his girlfriend. They might feel overwhelmed by all the attention and want a quiet life, so they run away.
Maybe Harry joins Voldemort because he discovers some dark secrets about the so - called good side in the wizarding world. He might think that Voldemort's way of ruling could bring a new order that is more just in his eyes. However, he soon realizes that Voldemort's true nature is far more cruel than he expected, leading to a conflict within himself.
Obviously, Harry Potter and Voldemort are the main characters. Harry, who makes the unexpected choice to join Voldemort. And Voldemort, who welcomes Harry into his ranks, perhaps with an ulterior motive.
This is a very strange and dark concept for fanfiction. In a possible plot, perhaps they are under some powerful mind - controlling spell. Maybe Voldemort has found a way to use their skills and knowledge for his own evil ends. For example, Harry's connection to the Deathly Hallows could be exploited, and Ginny's powerful magic, which was shown in the books, could be used to carry out Voldemort's orders against their will.