There could also be a group of traveling merchants who often cross paths with the witch. They could bring news from different parts of the world, and sometimes get caught up in the witch's affairs, adding a bit of comic relief to the fanfic with their bumbling attempts to deal with magic.
Another plot idea could be to put her in a situation where she has to team up with her enemies to face a greater threat. This would force her to set aside her differences and learn about her foes on a more personal level, leading to character growth for both her and the other characters.
Since I don't have first - hand experience with this particular visual novel, it's hard to say precisely. However, based on the title, it seems that Annerose is a central figure. 'Witch of Steel' gives the impression that she is a powerful and perhaps unyielding character. The visual novel may tell the story of her adventures, her battles, and her growth as a character. It could be set in a fantasy world with its own unique lore, and Annerose's actions and decisions could drive the plot forward, whether it's related to fighting against evil, protecting her loved ones, or fulfilling a grand prophecy.
You can try looking for it on popular digital game platforms such as Steam. Sometimes, visual novels are also available on official websites of the developers or publishers.
Sasuke could be a side character. Since Naruto is getting special training from Kakashi, Sasuke might feel jealous or motivated to train harder himself. Sakura could also be there, perhaps she tries to learn from Kakashi's training methods to help Naruto better. Another potential side character could be Iruka, who might check on Naruto's progress from time to time and offer some words of encouragement.
A young and ambitious mage who is trying to prove herself in a world dominated by warriors. She might face discrimination and have to fight not only her enemies but also the prejudices within her own society. She could be a main character as she tries to make a name for herself using her magical abilities in the 'a tale of blood and steel' setting.
One potential side character could be the Thenardiers. They might try to take advantage of Cosette's pregnancy, thinking they can get some money or favors from Marius and Cosette. Madame Thenardier could be especially devious in her plans. Another side character could be a kind midwife in the neighborhood. She would help Cosette throughout her pregnancy, giving her advice on health and child - rearing. And of course, Gavroche, Marius's little friend, could be around, bringing some cheer and a sense of innocence to the story.
The Ice King could be a side character in a comical way. He might try to disrupt their marriage in his zany attempts to get a princess for himself. Also, Flame Princess's father, the Flame King, could play a role. He might be initially hesitant about Finn but then grow to accept him as part of the family.
A wise old wizard could be a great side character. He could act as a mentor to the little king, guiding him in his use of magic and in making difficult decisions.
There could be characters from other regions or factions that we haven't met in the main story yet. Maybe some powerful mages or warriors from a far - off land.
There could be some original characters created by the fanfiction writer. For example, a mysterious mentor figure who has been secretly training Izuku in a special technique that he can use against All for One. This mentor could have their own backstory and motives that are intertwined with the main plot of the fight.