No. In the original 'Harry Potter' series, Harry is the hero who opposes the Death Eaters. Fanfiction might distort this, but it goes against the essence of the original story.
Another important theme is the exploration of the grey area between good and evil. In the original Harry Potter series, the divide between the good guys and the Death Eaters (the bad guys) is quite clear. But in fanfiction, authors often like to explore that middle ground. They show that not all Death Eaters may be completely evil, and Harry may have to make difficult decisions about who to trust and what is truly right or wrong in a more complex moral landscape that includes the Death Eaters.
Well, there's the theme of secrecy. Since the Death Eaters operate in the shadows, a lot of fanfictions play with the idea of hidden identities and secret agendas. Another common one is the theme of family. Some Death Eaters have family members who may or may not support their actions. And of course, the theme of good vs evil is always present, as the Death Eaters are on the 'evil' side in the wizarding world.
I don't think it's a popular fanfic concept. Harry Potter is known for his courage and determination to fight against Voldemort and his Death Eaters. The original story has built up a strong moral framework where the Death Eaters are the villains. Turning Harry into someone who is a fan of them would completely distort the character and the values that the series represents. Most fans would probably find it hard to accept such a deviation from the established canon.
In such a fanfiction scenario, it would completely颠覆 the original story. Harry would be on the side of evil, which means he might be involved in dark magic practices and attacking those he once considered friends and allies. It would be a very dark and扭曲的 version of the Harry Potter universe.
Perhaps it indicates that the character is in a state of transition. In the Harry Potter universe, Death Eaters can go through various changes. A blurry Death Eater might be someone who is in the process of fully becoming a true Death Eater. They could be struggling with their loyalty, and this 'blurry' state reflects their internal conflict. For instance, they might have some good in them still but are being pulled towards the dark side, and the author uses this blurry description to show that in - between state.
Yes, it can be quite a popular concept in some fanfiction circles. The idea of turning a heroic character like Harry into a Death Eater is a very interesting and controversial twist. It allows for exploring different aspects of the Harry Potter universe, such as what would happen if the power of the Dark Side had swayed him. It also makes for some very intense and dramatic storylines as his relationships with other characters would be completely upended.
The plot could develop in a very dark way. Harry might start hunting down the Order of the Phoenix members. He would be using his knowledge of the good side to help the Death Eaters. For example, he could lead them to the secret passages in Hogwarts.
He might use his power to defeat the Kishin more easily. The Kishin feeds on souls and is a major threat in Soul Eater. As Master of Death, Harry could have some special ability to either protect souls or directly combat the Kishin's power over them.