Since the title implies a girl is central to the story, she's definitely a main character. There could be other characters like a mentor figure who guides her in the Tekking 101 world. Maybe there are some opponents she has to face in the story. For all we know, there could also be a group of friends she teams up with in the context of Tekking 101, but without more information, it's just speculation.
Given the title 'Tekking 101 Manga Girl Story', the girl is surely one of the main characters. In addition, there might be a male character who is either her love interest or her rival in the Tekking 101 activities. There could also be an older, more experienced character in the Tekking 101 world who acts as a teacher or guide to the girl. However, this is all just guessing without more details about the actual story.
I'm not sure specifically what the 'Tekking 101 Manga Girl Story' is about as there isn't much information given just from this title. It could be a story about a girl in a manga that has some unique elements related to 'Tekking 101', perhaps a story about a girl who is into tekken - like fighting in a manga world.
Since we have no details about 'the 100 girl story', we can only guess. Maybe there is a leader among the 100 girls who is a main character. Or there could be a few girls who are different from the rest in some way, like having unique skills or personalities, and they are the main characters.
Perhaps it has a single protagonist, like a young girl with special powers. She could be the key figure in the story, using her powers to fight against evil forces or to solve mysteries in her world. There might also be some supporting characters, like her wise old mentor or her loyal animal companion.
Well, surely the girl herself is a main character. And probably her family members, like her parents or siblings who would be deeply affected by her vanishing. There might also be a detective or a police officer if it's a mystery - style story, as they would be trying to solve the case of her disappearance.
The main characters are the princess, the false maid, and the king. The princess is the true heir who is wronged, the false maid is the one who betrays her, and the king is the authority figure in the story.
Since I don't know the details of the 'girl for a day story', it's hard to say who the main characters are. But surely the girl herself is a main character. There might also be her family members, friends, or people she meets during that day.
The main characters are, as the title suggests, the girl and the fox. The girl is likely a curious and kind - hearted person. And the fox is an animal that has its own character traits, maybe it's clever or cautious.
The main characters are the girl and the lion, obviously.
Typically, the main character is the girl who is in the basement. And there is often another character, the person who put her there, like a captor or an abuser.
In Gunslinger Girl Story, the main characters include the young female assassins such as Triela. She is a key figure among the girls, with her own set of skills and emotions. The handlers, like Giuseppe, are also main characters as they are closely involved with the girls' lives, training them, and sending them on missions. There are other girls as well, each with their own distinct traits that are explored throughout the story.