It might be a little witch as the main character. She could be using the little broomstick to fly to her secret hiding places in the forest or to visit her magical friends. And of course, the little broomstick itself could also be considered a main character in its own right, with its own personality and quirks.
There could be a wizard as the main character. He might have received the little broomstick as a gift from his mentor. Along with the wizard, there could be a little magical creature, like a pixie, who tags along on the broomstick rides and helps the wizard in his adventures, so all of them could be main characters in the 'little broomstick story'.
Since I don't know the exact 'little broomstick story', it could be a young girl or boy who is the owner of the little broomstick.
I'm not sure specifically as there could be many stories related to a 'little broomstick'. It might be about a magical adventure where a little broomstick has special powers, like being able to fly and take the main character on exciting journeys through enchanted lands.
Often, the main characters are Harry and some of the Hogwarts professors. For example, Professor McGonagall could be involved. She might be the one who assigns Harry the task of polishing the broomstick in the first place, and she could be observing his progress and offering some strict but useful advice along the way.
Sometimes, there are wise old mentors. These characters have years of experience with broomstick flying and they guide the younger ones. They know all the secrets of different broomsticks and the best flying routes.
Obviously, Harry Potter himself is a common character. He is the main protagonist in the original series and often the central figure in fanfictions related to the broomstick as well. Hermione Granger and Ron Weasley also frequently appear, as they are Harry's closest friends and are usually involved in his adventures.
Harry Potter himself is often a great character in these fanfics. His natural talent on a broomstick can be explored further, like in a fanfic where he discovers new tricks on his Firebolt. Ron Weasley can also be interesting as he sometimes struggles with confidence on a broom, and a fanfic could show his growth in this area.
I don't have enough details about 'the little story' to say for sure, but it could be a child, a pet, or an old wise man.
In the chicken little characters story, the key character is Chicken Little, the one who believes the sky is falling. Another important character is Foxy Loxy, a rather sly animal. There are also other barnyard animals like Henny Penny and Ducky Lucky who are involved in Chicken Little's adventure when he spreads the word about the sky falling.
The main characters of 'little busters main story' are the boys and girls who form the Little Busters. Riki Naoe is a central character, being somewhat of a narrator in a way as we see the story through his perspective at times. Kyousuke Natsume is a charismatic figure in the group. Then there are other members like Masato Inohara and Kengo Miyazato. The female characters such as Rin Natsume also play significant roles in the story, adding different dimensions to the relationships and the overall plot.
The main characters are obviously the little boy and the little cat.
The main characters are Little Grey and Little White.