Maybe in the fanfic, Harry loses his temper when he discovers someone has betrayed his trust, like a false friend who leaked his secrets.
It could be that Harry loses his temper due to the unfair treatment he receives at Hogwarts. For example, if a teacher wrongly accuses him of something he didn't do, like cheating in an exam. His pent - up frustration from always being in the spotlight for the wrong reasons might cause him to explode in anger.
In this fanfic, it might be that Percy is in a high - pressure situation like a really difficult quest. Things keep going wrong, his team isn't listening to his plans, and he just loses his temper out of frustration. He starts yelling at his teammates, accusing them of not taking things seriously enough.
It could be Draco Malfoy. Malfoy is always taunting Harry and his friends. His constant insults and attempts to undermine Harry might finally push Harry over the edge and make him lose his temper.
One possible reason could be that he's constantly being underestimated or not given the credit he deserves. In some fanfictions, his friends might take his contributions for granted, which could lead to his temper flaring up.
One possible reason could be bullying. If Percy is constantly being picked on by other students, it might push him to lose his temper. Maybe they tease him about his appearance, his family, or his abilities. Another reason could be academic pressure. If he's struggling with his studies and feels like he can't keep up, it could lead to frustration and ultimately a loss of temper.
His own self - doubt could be the cause. Percy might be constantly thinking that he's not good enough to protect his friends or complete his quests. And one small trigger, like a friend making a harmless joke about his capabilities, could make him lose his temper because it hits too close to home.
In 'Harry Loses His Emotions Fanfiction', it could be that Harry experiences a really traumatic event. Maybe he witnesses the death of a very close friend in a battle. This shock is so great that it makes him shut down his emotions as a self - defense mechanism. He then becomes cold and distant, and the story could be about how his friends struggle to reach the old Harry again and help him heal.
Maybe in the fanfiction, Harry's twin could be lost in a magical accident. For example, during a wizarding battle, the chaos causes them to be separated, and Harry spends the rest of the story trying to find his twin.
Well, perhaps it's set in a post - apocalyptic world. Carl is in a fight with some bad guys, and during the struggle, he loses his eye. The fanfic could focus on his journey to get revenge while also learning to live with his disability.
Arthur could be the cause. He often bosses Merlin around and doesn't fully understand Merlin's capabilities. His constant demands and lack of respect for Merlin's intelligence might push Merlin to the edge. For instance, when Arthur makes Merlin do dangerous and pointless tasks without any regard for his safety.
In this fanfiction, it could be that the pressure of being 'The Chosen One' finally gets to Harry. All the battles, the losses he has endured, and the constant threat of Voldemort might push him over the edge. He could start acting erratically, pushing away his friends and allies because he no longer trusts his own judgment.