The main characters could be a young adventurer who stumbles upon the blue dragon and the delphinium. Or perhaps a wizard who has been studying the delphinium's magical properties and then has an encounter with the blue dragon.
One possible main character could be a healer. In the world of the fanfic, the delphinium might have healing properties that the healer is trying to understand. And then the blue dragon enters the scene, either as a threat or as an ally. Another option is a young girl or boy from a small village. They have heard tales of the blue dragon and the delphinium all their lives and finally decide to seek them out, thus becoming the central figure in the story. There could also be an old sage who has knowledge about both the blue dragon and the delphinium and plays a crucial role in the events of the fanfic.
Some common themes might include adventure. Since the Blue Dragon could be seen as a powerful and mysterious element, it might lead characters in the fanfic on exciting adventures. Also, themes of magic could be present as delphiniums are often associated with beauty and perhaps some magical properties in a fictional context.
The main characters would surely be Owen and Blue. Owen as the human who has a special relationship with Blue, and Blue as the pregnant one. Additionally, there could be some other dinosaurs that Blue interacts with. For example, her mate (if she has one) could be another important character, and their relationship could add more depth to the story of the pregnancy.
Obviously, Prof Oak would be one of the main characters. And perhaps a young trainer who is helping Prof Oak in his research related to the blue 39 thing. It could be a trainer who has a special bond with a certain type of Pokemon that is somehow related to the mystery.
A wise old hermit could be a main character. The hermit, living in seclusion, has knowledge about the dragons that no one else does. When the last dragon comes to him for help, he uses his wisdom and his connection to nature to guide the dragon on a journey to restore its species, all while facing various challenges along the way.
The obvious main characters would be the donkey and the dragon.
A brave knight could be a main character. They might be on a quest to find the dragon knot to save their kingdom from a dragon threat, believing that the knot holds the key to controlling the dragons.
Maybe a new Saiyan who was born on a different planet and has a different understanding of Saiyan culture. He or she could come to Earth and interact with the existing Dragon Ball characters, bringing new fighting styles and a fresh perspective to the story.
The main characters are Blue and Pearlven, of course. Blue is often depicted as a brave and curious character, while Pearlven is more of a wise and calm one.
I'm not sure specifically who the main characters are in 'blue flowers fanfic' as there could be many different versions. But it's likely that there are characters who are either drawn to the blue flowers or have a special connection with them.
I'm not sure who the main characters in 'blue skies fanfic' are as it depends on the specific fanfic. It could be original characters created by the fanfic writer.