There are also cases where the protagonist is someone who had a strong sense of justice in their previous life. They are then determined to make the House of the Dragon world a better place, by fighting against the corrupt nobles or trying to end the wars that plague the land.
Often, it's an ordinary person from our world who is reincarnated. They might be a big fan of the House of the Dragon in their previous life and now find themselves in this new, dangerous world.
One interesting concept could be the character's knowledge from their previous life affecting their actions in the House of the Dragon world. For example, they might use modern strategic thinking to navigate the complex political situations in the story.
Another theme is changing the story. Reincarnated characters often try to change the events that happened in the original Dragon Ball plot. They might prevent certain deaths or form different alliances. For instance, they could try to stop Vegeta from being evil in his early days in the series.
In this type of fanfiction, the dragon's family members can be popular characters. If the dragon has siblings or a parent in the story, their relationships are often explored. For example, a protective older dragon sibling can add a lot of drama and warmth to the story. Also, there are sometimes villainous characters like dark mages who try to capture or control the dragon, and they can be very engaging as well.
Well, a typical plot element could be the exploration of the dragon's powers. In many of these fanfictions, the reincarnated character spends time learning about the different abilities they now possess as a dragon. There's also the aspect of making allies or enemies among other dragons. Some stories might include a search for a way to return to their previous form, while others focus on the character fully embracing their new dragon life and using it to their advantage.
Sakura also often appears. She might be confused by the changed behavior of the reincarnated Sasuke. Maybe the reincarnated Sasuke is more open and friendly towards her than the original Sasuke, which would lead to different interactions between them.
The most interesting characters can vary. Some fanfictions have dragon hatchlings that the reincarnated character takes under their wing. These hatchlings are full of curiosity and naivete, which contrast with the more jaded world of adult dragons. Then there are the dragon hunters. They add an element of danger and conflict as they are constantly on the prowl for dragons. Their motives can range from simple greed to a more complex vendetta against dragons, and their interactions with the reincarnated dragon can be intense.
Well, of course, the main character who is reincarnated as a kaiju. There are often scientists or military personnel who are trying to deal with the appearance of the kaiju. Some fanfictions might also have other kaiju as characters, either as friends or foes to the reincarnated kaiju.
The protagonist is of course a common character. Usually, they are someone who has a deep love for games in their previous life. There are also often mentors or guides in these stories. They could be an old wizard or a powerful knight who helps the protagonist understand the new world.
The most common character is obviously the tree itself. Then there are often animals like birds, squirrels, or deer that interact with the tree. Sometimes, there might be a forest spirit or a dryad that has a special connection to the tree. There could also be humans, such as a woodcutter or a wandering traveler who stumbles upon the tree.
Well, of course, Goku is a very common character. Since the story is about being reincarnated as a Saiyan, Goku's presence is often there either as a mentor or as a benchmark for the main character's power level.