In many novels with such a premise, the 'rival' often has his own motives and backstories that lead to this situation. For example, he might have been wronged in the past and sees the hero as an obstacle to his revenge or to achieving his goals. The plot could also explore how the two characters grow and change through their rivalry, and whether they will eventually reach some sort of understanding or remain enemies.
I'm not entirely sure about this novel in particular. But often in this type of story, the 'rival' character has their own backstory that led them to become the hero's adversary. It could be that they come from a different background, like a poor upbringing while the hero is from a privileged one. This disparity might fuel their rivalry, and as the story progresses, they might either find a way to reconcile or the rivalry could escalate to a point of no return.
Eventually, Eren might start to investigate the reasons behind Mikasa's betrayal. If he discovers that there are more complex factors at play, like she was forced or there was a misunderstanding, he could feel a mix of guilt for his initial reaction and relief that their relationship wasn't as broken as he thought. However, if he finds out that she truly betrayed him out of her own will, he might become even more determined to carry out his plans, whatever they are, without her.
There could also be other supporting characters. Maybe there is a love interest that both the hero and the rival are vying for. Or there could be a mentor figure who has influenced either the hero or the rival. Another possibility is that there are sidekicks for each of them, who play important roles in their respective quests and in the rivalry between the two main characters.
Since I haven't read the novel, it's hard to say for sure. But surely there's the main character who has become the hero's rival. And of course, the hero. There may also be side characters like friends or family of either the rival or the hero who play important roles in the story.
Some fans are heartbroken. Eren is a very popular character, and his death can be a huge emotional blow. They might write comments expressing their sadness and disappointment.
Well, without having read the exact novel, it could potentially be about a woman who marries a man with a son (the hero). Maybe she has to deal with the challenges of being a stepmom while also being involved in the hero's adventures or growth. For example, she might help him discover his powers or face his enemies in some way.
I'm not sure about the specific plot of this novel as there could be many different interpretations. But generally, it might involve a woman becoming the stepmother of a hero figure. There could be themes of family dynamics, love, and the challenges that come with such a role in a heroic or fantastical setting.
I'm not sure specifically as there could be many different stories with this title. It might be about a woman who somehow finds herself in the role of the mother of a hero, perhaps dealing with the challenges of raising a child who is destined for great things.
The main characters would include the stepmom who has to navigate her new role. The hero, who is on a path of growth and heroism. Then there could be other supporting characters like the hero's friends or mentors. Maybe there's an antagonist who tries to disrupt the family or the hero's journey, which would also make that character important in the story.