Since we don't have much information, they could be a diverse group of girls. They might have different abilities, personalities, and backgrounds. Some could be strong and fearless leaders, while others might be more timid but with hidden powers that are revealed during the battles. Maybe there are some who are outcasts trying to prove themselves, or popular girls who have a reputation to uphold in these battles.
I don't know exactly as there isn't enough information given. But I assume they are girls who are involved in the battles.
I'm not sure specifically as it depends on the actual story. But it could be the same main characters from 'Girls x Battle 2' like the female warriors or leaders in that game world.
It's a game or a story collection that might involve girls in battles and their side stories. But without more context, it's hard to be very specific.
Some of the main characters are the various monster girls. Each type of monster girl, like the lamia or the harpy, can be a central character in different side stories. They bring their own personalities and traits to the story.
It's possible that there are other magical girls or boys in the side story too. They could be from different regions of the magical world, each with their own set of powers and personalities. Maybe there's a rival magical girl who at first seems like an enemy but later becomes an ally. And don't forget about the villains. There could be a powerful dark sorcerer or a group of mischievous imps causing trouble in the magical girl's side story world.
The main character is usually a male protagonist who embarks on the journey in the world of monster girls. There are also various monster girl characters, such as the lamia, harpy, and slime girl, who play important roles in the story, either as allies or antagonists depending on the situation.
Since we don't have much information, the main character is surely the girl. There might be librarians as supporting characters, and perhaps other library patrons or friends of the girl could also be part of the story.
I'm not sure specifically as it depends on the particular side story. But it could be some popular monster girl characters from the main Monster Girl Encyclopedia, like the lamia or the harpy.
There are Tony, a guy with a past in the Jets. Then there's Maria, a young and passionate girl who is related to the Sharks through her brother Bernardo. Also, Riff, who is a key figure in the Jets and helps drive the conflict between the two gangs. These characters play crucial roles in the story, with Tony and Maria's love story at the center and Riff fueling the gang - related tensions.
I don't know the '340 days side stories' well enough to name the main characters. But usually in a story, the main characters are the ones driving the plot forward, so they could be the ones facing the most significant challenges or having the most growth during the 340 days.
It might be an old storyteller who is the central figure. He knows all the tales of the east side, from its founding to the present day. He passes on these stories to the younger generation, keeping the history and culture alive.