Perhaps they fall in love in a fanfiction. Senri could be the one to break through Rima's cold exterior. They could have a story where they are forced to hide their relationship from the rest of the vampire community because of some old - fashioned rules. In this story, they would have to find ways to be together in secret, which would add a lot of drama and tension.
In a fanfiction, Senri and Rima could team up to solve a mystery within the Vampire Knight world. Maybe there are strange disappearances among the vampires and they suspect foul play. They use their individual skills, like Senri's strength and Rima's agility, to track down the culprit. Along the way, they learn more about each other and grow closer as friends or perhaps something more.
One interesting plot idea could be that Rima and Senri go on a secret mission for the vampire council. They have to face a group of rogue vampires who are threatening the peace between vampires and humans. Along the way, they discover a long - hidden power within themselves that helps them in the fight.
A plot could be that Senri and Rima get separated from their vampire group during a battle with a rival group. They have to rely on each other to survive in the wild and find their way back. This would force them to communicate and understand each other better.
Another way to develop their relationship is by having them face a conflict within the vampire community. Maybe there is a new rule that they both disagree with. Standing up together against this rule would strengthen their bond. Senri could be the more hesitant one at first, but Rima's determination could inspire him, and they would grow closer as they fight for what they believe in.
One possible fanfiction could be about Senri and Takuma going on a secret adventure in the Vampire Knight world. Maybe they discover a hidden part of the school that holds a powerful vampire relic. They have to work together to keep it safe from those who would use it for evil purposes.
A story could be about Rima and Shiki exploring an ancient vampire tomb. There, they find clues about their vampire lineage that they didn't know before. This discovery could change their relationship as they realize they are more connected than they thought.
In a fanfiction, Rima and Shiki could start as rivals. Rima might see Shiki as a threat to her position among the vampires. But then, they get paired up for a task that requires them to work together. As they spend time together, they start to understand each other better. Shiki realizes that Rima is not as cold as she seems, and Rima sees that Shiki has a kind heart beneath his tough exterior.
They could be paired up for a school project in the Vampire Knight world. Senri, who isn't very talkative, and Takuma, who is more outgoing, would have to find a way to work together effectively. This could lead to some comical situations as Senri tries to keep up with Takuma's enthusiasm.
Some fanfictions focus on Senri and Takuma's friendship evolving over time. For example, they start off as just acquaintances but as they face various challenges together, like protecting a human they both care about from other vampires, their bond grows stronger and they become true friends who would do anything for each other.
One common theme is his relationship with other characters, especially his friendships or rivalries. For example, his interactions with the main characters can be a central focus, exploring how he fits into the complex world of Vampire Knight.
A common theme is adventure. They often go on adventures together, exploring hidden parts of the vampire world. This could involve seeking out ancient vampire artifacts or trying to find a safe haven for a group of outcast vampires.