Well, without having read 'kanojo ga flag wo oraretara light novel', it's hard to say precisely. However, light novels usually have elements like character development, a central theme. Maybe in this one, the girl (kanojo) has something to do with the concept of 'flag' which could be symbolic in the story's context, like a signal for an event or a change in the plot. It could also be about her achieving or encountering something related to these 'flags' in a fictional world filled with various situations and other characters.
Since I don't know the exact details of this 'kurau harry potter fanfiction', it could be about many things. It might be a love story between a character from Kurau and one from Harry Potter. Or it could be an adventure story where the characters team up to fight a common enemy. It could also be a story that focuses on the friendship between characters from the two different series and how they learn from each other's worlds.
You can try looking for it in local bookstores that carry a wide selection of light novels. Some large chain bookstores might have it in their international or Asian literature section.
The title suggests that it could be a story full of adventure. Since the main character can read manga and is considered the world's strongest in the light novel world. There may be battles where the protagonist uses the knowledge or skills gained from reading manga to defeat enemies. It might also explore different fictional worlds within the manga that the character can access or is influenced by.
You could try looking on popular fanfiction websites like FanFiction.net or Archive of Our Own (AO3). These platforms usually have a large collection of fan - created works, including crossovers like 'kurau harry potter fanfiction'. Just use their search functions to see if you can find it.
I'm not entirely sure as I haven't read it specifically. But generally, a light novel often has elements of fantasy, adventure, and character - driven stories. It might be about the voices of the stars, perhaps a story set in a science - fiction universe where the stars play a significant role, like they could be sentient or hold some kind of power.
I'm not entirely sure as it could be a rather niche or new visual novel. It might be about various themes like mystery, relationships, or a unique fictional world. Without more information, it's hard to say precisely.