It could be due to a misunderstanding. Perhaps there was some miscommunication between them. Like Jace made a decision without consulting Alec, and Alec felt left out or disrespected. Or it could be related to their family or past issues resurfacing. For instance, something from their childhood that they have different views on now.
One possible reason could be jealousy. Maybe they both have feelings for the same person in the fanfic. Another reason might be a difference in their approaches to a mission or a problem they are facing. For example, Alec might be more cautious while Jace is more impulsive.
In the fanfic, it might be about power or leadership. If there is a situation where they need to lead a group, they could have different ideas on how to do it. Alec may believe in a more democratic approach while Jace thinks a more authoritarian style would be better. This could lead to a big argument between them.
Another reason could be loyalty issues. For example, if one of them is suspected of being too friendly with the enemy or making a deal that the other doesn't approve of. In a complex world of fanfic - created politics and relationships, this can be a major cause for a fight.
It could make other characters take sides. For example, if they have a mutual friend, that friend might feel pressured to choose between Alec and Jace. Some characters might distance themselves from both of them to avoid the drama.
One possible reason could be that the fanfic contained disturbing or offensive content. Maybe it had themes that made some people uncomfortable, like excessive violence or inappropriate relationships. So, seeing it led to an argument.
In the fanfic, it might be a fight that's more about pride and proving who is the better Shadowhunter. Alec has his own set of skills and Jace has his. They might get into an argument about who is more useful in a certain situation, and it turns into a full - blown fight. Alec might use his strategic mind and archery skills, while Jace uses his speed and swordsmanship.
Well, sacrifice is a theme that pops up often. They would do anything for each other, even put their own lives at risk. This is seen in 'The Ultimate Sacrifice' fanfic. Additionally, growth is a common theme. As they face different challenges, they grow as individuals and as a duo. Their relationship is always evolving in the fanfics, which makes it really interesting to read.
Another reason could be their different career aspirations. Suppose Taebyung was aiming for a high - paying corporate job with long hours and a lot of stress but great financial rewards. The reader, however, might be more interested in a creative career like painting or writing, which didn't offer much financial stability at first but provided more personal fulfillment. They could argue about which career path was more valuable in life. Taebyung might think financial security was the most important thing, while the reader could believe that following one's passion was crucial.
One possible reason could be a difference in their leadership styles. Jason, being more of a traditional leader, might clash with Percy's more instinct - based leadership. For example, when planning a mission, Jason would want a detailed, step - by - step plan while Percy might be more inclined to 'go with the flow' and improvise as they go. Another reason could be over a girl. Maybe they both have feelings for the same demigod girl and their jealousy gets the better of them, leading to an argument.
One reason could be miscommunication. Maybe they didn't fully understand each other's needs and wants. For example, Alec might be too focused on his shadowhunter duties and not give enough time to Magnus, who would then feel neglected.
One popular theme is loyalty. Since they are parabatai, their unwavering loyalty to each other is often explored. Another theme could be sacrifice. For example, they might be willing to sacrifice their own desires or safety for the other. And friendship is also a big theme. Their deep bond as parabatai and friends can be shown in different ways like how they support each other through tough times in the fanfic.
They could just sit down and talk it out. Once they realize that they were both acting out of misunderstandings or emotions, they might simply apologize and go back to being friends.