Mages are also common. They can use their magic to either attack the dragon, create defenses, or try to communicate with it in some cases.
There are often brave knights. These are the ones who are usually at the forefront of the conquest, with their swords and shields ready to face the dragon.
And don't forget about the dragon itself. Sometimes it's portrayed as a mindless beast, but in other fanfictions, it can be a complex character with its own motives, like protecting its lair or its young. There might also be side characters like the villagers who are affected by the dragon's presence or the king who orders the conquest.
One of the most common supporting characters is Oichi. She often appears in fanfictions related to Masamune as she has a connection with him in the Pokemon Conquest universe. Another is Hideyoshi. His presence adds political intrigue as he may be an ally or a rival to Masamune. Also, many fanfictions include various Pokemon trainers from different regions. They can act as friends, rivals or even advisors to Masamune, helping him in his battles and decision - making processes.
The dragon itself is, of course, a common character. Whether it's in its original form at the start or in its reincarnated state.
In many betrayed dragon fanfictions, there are other dragons too. Sometimes a dragon's mate can be a character. For example, in a story where a male dragon is betrayed, his female mate might be searching for him or trying to avenge him. There could also be dragon hatchlings as characters in cases where the betrayal affects the whole dragon family.
The dragon itself is, of course, a common character. There are often dragon keepers or handlers in these stories too. They take care of the dragon during the egg - laying process.
Spyro is obviously the main character. Then there could be characters like Sparx, his dragonfly friend, who might play a role in the harem dynamic. Also, there could be female dragon characters created specifically for the harem idea, each with their own unique personalities and abilities.
Harry Potter himself is very common. Writers often put him in situations involving dragon spirits to see how he would react and grow. Hermione Granger is also popular as she could use her intelligence to study the dragon spirit, perhaps trying to understand its magic or origin.
Naruto himself is often a common character. Since he is the main protagonist of the original series, it's natural for him to be involved in fanfiction about a new and powerful element like the Dragon Eye. Sasuke is also common, as his rivalry with Naruto can be extended into the story around the Dragon Eye. Kakashi might also appear frequently as a mentor figure who can guide the characters dealing with the new power.
Often, Harry Potter himself can be a character in these fanfictions. He might discover his hidden talent for taming dragons. Hermione could also be there, using her vast knowledge to help with the dragon - taming process. Ron could be the one who is initially scared but then warms up to the idea. And of course, Hagrid is likely to be involved as he has a great love for magical creatures, especially dragons.
Harry Potter himself is often a central character in these fanfictions. Since he was the one who originally faced the dragon task in the Triwizard Tournament, many fanfic authors like to explore different scenarios with him in the same situation.
Chi - Chi is often a key character. As Goku's wife in the original series, she has a significant role in fanfictions too. She can be shown in different ways, sometimes being more protective or sometimes more involved in Goku's adventures with his harem - like group.