One possible antagonist could be the Akatsuki members. They are always looking for strong opponents or valuable information. Maybe they target Iruka because they think he has some knowledge about Naruto that they can use, and Kakashi has to stop them.
In such a fanfiction, perhaps Kakashi might save Iruka from a dangerous enemy like Orochimaru's minions. Kakashi, with his Sharingan and powerful jutsu, could arrive just in time to fend off the attackers.
One common theme is the bond between teacher and student. Iruka, as Naruto's teacher, saves him not just physically but also emotionally. Another theme could be redemption. Iruka's actions might lead to Naruto's redemption in some way, like saving him from a dark path. And of course, there's the theme of heroism. Iruka becomes the hero in Naruto's life at that moment of saving.
Kakashi and Iruka could start off with some initial tension. Iruka might be a bit wary of Kakashi's unorthodox teaching methods as he's more traditional. But as they work together with Naruto, they would start to understand each other better. Kakashi would share his combat experiences with Iruka, and Iruka would share his insights on Naruto's emotional state. Naruto would be the bridge between them, bringing out the best in both.
One possible plot could be a training adventure. Naruto, Kakashi, and Iruka could go on a special mission to train Naruto further. Kakashi might teach Naruto some new and advanced ninja techniques, while Iruka could offer moral support and his own knowledge of basic ninja skills. They could face a new and dangerous enemy, and through their combined efforts, Naruto could learn important lessons about teamwork and self - improvement.
One possible plot could be that Kakashi and Iruka notice Naruto's loneliness more acutely than in the original story. They decide to formally adopt him. Kakashi might train Naruto more intensively in his own unique ways, while Iruka helps Naruto with his schoolwork and emotional growth. Naruto would then grow up with a stronger support system and become even more confident and powerful at a faster rate.
There are many 'iruka saves naruto fanfiction' out there. One popular one might be on platforms like FanFiction.net. You can search for it using the tags 'iruka', 'naruto' and'saves'. Usually, these fanfictions show Iruka coming to Naruto's rescue in various dangerous or emotional situations within the Naruto universe.
Perhaps a plotline where Kakashi and Iruka have to protect Naruto from the Akatsuki. They train Naruto intensively to prepare him for any potential attacks. At the same time, they try to keep Naruto's identity as the Jinchuriki of the Nine - Tails a secret from the Akatsuki members who are after his power.
They are a popular pairing because they have a pre - existing relationship in the Naruto series. They are both important figures in the lives of the young ninjas. Kakashi is a respected and skilled jounin, and Iruka is a caring teacher. Their different personalities complement each other well. Kakashi is more reserved and mysterious, while Iruka is warm and open. This contrast makes for interesting storylines in fanfiction.
One possible plotline could be Iruka and Kakashi trying to teach Naruto different ninja skills in their own unique ways. For example, Kakashi might focus on more advanced combat techniques while Iruka helps Naruto with the basic ninja knowledge. Another plotline could be them dealing with Naruto's pranks and how they discipline him in a loving yet firm manner. Maybe they also have to protect Naruto from some of the more dangerous elements in the ninja world that target him because of his status as the Jinchuriki.