Kurumu would be heartbroken. She has been in love with Tsukune for a long time. His death would make her feel lost and alone. She might withdraw from the others and become more solitary, constantly mourning his loss.
Moka would be devastated. She has a strong bond with Tsukune, and his death would likely send her into a deep state of grief and anger. She might go on a rampage seeking revenge against whoever or whatever caused his death.
One possibility could be that Tsukune's death is a sacrifice to save his friends. In the Rosario Vampire world, he has made many friends and perhaps in the fanfiction, a powerful enemy threatens them all. Tsukune, being the selfless character he is, might give his life to ensure their safety. For example, if a dark and ancient vampire or a powerful monster attacks the school, Tsukune could use his unique powers (a combination of human and vampire abilities) in a final, all - out attack that costs him his life.
First, know the characters well. Tsukune is a complex character with his own growth arc. Make sure to stay true to his personality. Also, understand the world of Rosario Vampire, like the different monster species and their cultures. Then, come up with an interesting plot. It could be a new adventure for Tsukune or a different take on his relationships.
His friends would be devastated. May, for instance, would probably be in deep shock and denial at first. She might remember all the times they had competed and the little moments they shared. Then she would likely turn her grief into determination to carry on his legacy in the Pokemon world.
It could be really exciting. Tsukune with Saiyan powers would be super strong. He might have the ability to transform and his battles would be intense. Maybe he would use his Saiyan strength to protect his friends in the Rosario Vampire world from new and powerful enemies.
Ginei would be a bit more reserved in his reaction. He might offer some practical advice from his own experiences or knowledge. He'd also be there to protect them if any threats came their way during the pregnancy, as he values their friendship.
Tsukune's vampire form in fanfiction can vary greatly. Some authors might focus on the emotional aspect of him dealing with this new side of himself. He could struggle with the urge to feed on blood, or he might embrace it as a part of his new identity. Additionally, his relationships with other characters, especially Moka, can be significantly affected by his vampire form.
Rosario Vampire might be intrigued. It could be fascinated by the unique characters and abilities in Naruto's world.
Tsukune could fit in as an outsider with unique abilities. His vampire powers would be a contrast to the ice - based powers in the Sub Zero world. He might be initially seen as a threat or a curiosity.
Tsukune's vampire form in fanfiction is sometimes depicted as a symbol of his evolution. He starts as a normal human in the Rosario Vampire world, and as he transforms into a vampire, he represents a bridge between the human and vampire worlds. Writers use this form to show how he can navigate and change the dynamics between the two species.
Tsukune's moral compass might shift. Ghouls in many stories have a more amoral approach to survival. Tsukune would have to fight against this natural inclination of his new form. He might start to question the values he once held dear and have to re - evaluate his place in the world of Rosario Vampire, trying to find a way to be a 'good' ghoul in a world full of different and often conflicting species.