Well, the Naruto characters in a Highschool of the Dead - Rei fanfiction would have a range of reactions. The more hot - headed ones like Rock Lee would charge into battle with the zombies, showing off his taijutsu skills. However, the more diplomatic characters like Kakashi would try to establish order among the survivors, which would include Rei. They would also be interested in learning about Rei's world and how she has survived so far. They might even try to find a way to use the chakra system to combat the zombie plague, seeing it as just another form of evil to be defeated.
Some Naruto characters would likely be very confident in a Highschool of the Dead - Rei fanfiction setting. For example, Naruto himself would probably jump right into action against the zombies. He'd see it as another challenge to overcome and would use his Rasengan or other jutsus without hesitation. Sasuke, on the other hand, would be more calculating. He'd analyze the situation of the zombie apocalypse and the role of Rei and others before making a move.
In a Naruto and Highschool of the Dead fanfiction, Rei could have an interesting role. Maybe she could possess some ninja - like skills similar to those in the Naruto universe. For example, she might be able to use chakra in a way that is unique to her character, perhaps using it to enhance her physical abilities during the zombie apocalypse that is central to Highschool of the Dead. This would make her a more formidable fighter and could lead to some really cool action scenes in the fanfiction.
Naruto would probably be the first to jump into action. He'd be shouting about not giving up and trying to protect everyone. He might see the zombies as just another type of enemy to defeat. Sasuke, on the other hand, would be more cautious and calculating, looking for ways to use the situation to his advantage. Sakura would be using her medical skills to help the injured, while also fighting off zombies when necessary.
Sakura would be devastated. She has always had deep feelings for Naruto, whether it was friendship or something more. She would probably throw herself into her medical work even more, trying to find a way to bring him back, even if it was impossible. Shikamaru, being one of Naruto's friends, would be solemn. He might use his intelligence to figure out what really happened to Naruto, and he would be the one to come up with a plan to deal with the aftermath.
If we consider the Sharingan ability from Naruto, a character like Sasuke could use it to predict the movements of the zombies more accurately. This could be combined with the strategic thinking of the Highschool of the Dead characters. They could plan out how to best use Sasuke's ability to avoid large groups of zombies or to lead them into traps. The Highschool of the Dead characters might also learn some basic ninja stealth techniques from the Naruto characters, allowing them to move more quietly through the school corridors filled with zombies.
Issei, being the hot - blooded character he is, would probably be excited to meet someone as powerful as Naruto. He might challenge Naruto to a friendly spar at first, hoping to learn from him and test his own strength. And as he gets to know Naruto better, he could start to see him as a brother - in - arms, especially if they face common enemies together.
Some characters might be intrigued. For instance, Issei might be curious about Fem Naruto's fixation on Ophis. He could see her as an interesting addition to their world and might try to understand her motives. Rias, on the other hand, might be more cautious. She would likely be concerned about how Fem Naruto's admiration for Ophis could affect the balance of power in their territory.
Issei would probably be the first to want to fight Thanos. He's always eager to prove himself and protect his friends. He might initially underestimate Thanos due to his own growing power and confidence, but soon realize how powerful Thanos really is. Rias would be more cautious. She would likely try to gather information about Thanos first and then formulate a plan to either fight or negotiate with him.
For a 'Naruto x Highschool of the Dead' fanfiction, Naruto is a must - have main character. His presence is what makes the crossover unique. Among the 'Highschool of the Dead' characters, Saya Takagi would be an important main character. She's intelligent and resourceful. Naruto and Saya could make a great team. Naruto with his brute force and Saya with her brains. Then there's also Kohta Hirano, the gun - loving otaku from 'Highschool of the Dead'. He could be in awe of Naruto's powers and they could collaborate in battles against the zombies. Naruto could learn about modern firearms from Kohta, while Kohta could learn some ninja tricks from Naruto.
Obviously Naruto would be one of the main characters. He's the protagonist of the Naruto series, so he'd likely be at the center of the action in this fanfiction too. He'd be using his ninja abilities to combat the threats in the high - school - turned - zombie - land.
He would probably also bring his ninja values with him. In a world full of power - hungry devils and angels, Naruto's values of friendship, hard work, and protecting the weak could have a big impact. For example, he might try to reform some of the more villainous characters by showing them the value of these things. He could also form strong bonds with the main characters in Highschool DxD, like Issei, based on shared ideals of fighting for what's right.