Since I don't know the exact 'little horus short story', if it's related to Egyptian mythology, the main character would be Horus. There might also be his mother Isis, who is often an important figure in stories related to Horus. Another possible character could be Seth, who is sometimes in conflict with Horus in the mythology.
Horus is a main character. He was once a great and noble leader but was corrupted. Another is Leman Russ, the Primarch of the Space Wolves legion. He is known for his fierce loyalty and warrior spirit.
The 'little horus short story' could potentially revolve around the character Horus in his childhood. It might depict his relationships with other characters. For example, he could have friends or family members in the story. It may also include some lessons he learns or quests he undertakes. If it's based on Egyptian mythology, Horus is often associated with the sky and kingship, so perhaps the story could touch on those aspects in a more juvenile context, like how he discovers his powers related to the sky.
The main character is Horus, of course. He is a powerful and complex character. Besides him, characters such as Maloghurst are also significant. Maloghurst is sort of like Horus's right - hand man. And then there are the Space Marines who are loyal to Horus at the start. They are all part of this story that unfolds in the 'Horus Rising Graphic Novel', with their own personalities, loyalties, and motives that interact and collide as the plot progresses.
The main characters might include the person who first wields the little knife. This could be someone with a unique background or skill. There could also be a character who is in search of the knife for some important reason, like it holds the key to a long - lost treasure or it has the power to break a curse. Additionally, there could be a group of characters who are affected by the actions related to the little knife, for example, a community where the knife has some symbolic meaning.
As I don't know the 'little birds short story', I can't say for sure who the main characters are.
The main characters are the three bears (papa bear, mama bear, baby bear) and Goldilocks.
The little mermaid is obviously a key character. She is the one whose journey we follow. The human prince is the object of her love. He is a noble figure that the mermaid admires from afar and then tries to be with. And the sea witch is a very important character too. She is the one who enables the mermaid's transformation but also puts her in a very difficult situation with her strict conditions.
Perhaps the main characters are individuals who have committed some minor wrongdoings at a young age. They could be from a small town or community where their actions are noticed and judged. Maybe there is a leader among them who instigates most of the 'sinful' behavior and then there are others who follow along, either willingly or reluctantly.
I'm not sure as I haven't read it, but I assume the little fish is one of the main characters. There might also be other fish or sea animals like a big shark that could be a threat, or a friendly turtle that helps the little fish.
The main characters are the little mermaid herself, the human prince, and the sea witch.