I'm not sure specifically as there could be many different interpretations in such a fanfiction. It might involve a character named Rito facing a stabbing incident, perhaps in a battle, a crime scene, or a situation of betrayal.
Chuuya is not dead in the manga. The author has kept him alive to drive the story forward and create interesting developments. His presence adds a lot of excitement and intrigue to the plot.
It could be a rogue angel. There are always some angels in the Supernatural universe who oppose Castiel's ideas or actions, and they might see stabbing him as a way to get rid of him or send a message.
In such fanfiction, characters might show shock. For example, Dean could be horrified when he sees Castiel stabbed, his eyes wide open and his face pale.
Well, in 'naruto gets stabbed fanfiction', it could be that Naruto is exploring a new and dangerous area where he encounters a powerful and hostile ninja. In the heat of the fight, this ninja manages to land a stabbing blow. It might also be that Naruto is weakened due to some prior injury or chakra depletion, making him more vulnerable to being stabbed by a regular enemy. And, there could be a situation where Naruto is under the influence of some sort of genjutsu that impairs his ability to defend himself and thus gets stabbed.
Perhaps he gets stabbed as a part of a plot to take over his company. His rivals could be behind it, seeing his success as a threat. In the fanfiction, this could lead to a great revenge story where Kaiba has to regain his power and seek justice.
It might be a jealous rival. If Sakura is popular or has something that others envy, like a special talent or a relationship, a rival could have stabbed her out of envy.
Chuuya is a popular character. In chuuya and oc fanfiction, the original character (oc) often interacts with Chuuya in unique ways. It could be a story of adventure where the oc teams up with Chuuya to face various challenges. For example, they might battle against powerful enemies in a fictional city. This type of fanfiction allows fans to explore different relationships and storylines that are not part of the original canon.
Sure. Chuuya has made appearances in certain light novels. These appearances often add depth to his character and contribute to the overall storylines.