A really cool plotline could be that the owl summons are connected to an ancient and powerful clan that was long forgotten. Naruto, through his contract, discovers the secrets of this clan and their unique chakra techniques. He then has to learn and master these techniques to protect the village from a new threat. The owls could also act as messengers between Naruto and this hidden clan, and he has to prove himself worthy to the clan elders by using the owls' abilities in creative ways.
Well, in some fanfictions, Naruto having the owl summoning contract could lead to him being involved in a whole new set of missions. Maybe he's sent on secret espionage missions with his owls, who can fly silently and undetected at night. Also, the owls could be used in combination with his other jutsu. For instance, he could use shadow clones and then send the owls to different locations with the clones on their backs to cover more ground during a search for something or someone.
One plotline could be that Naruto uses the bird summons to explore uncharted areas. He discovers new hidden villages or ancient ruins that are only accessible by air. Another could be that the bird summons have a special connection to a long - lost clan's secrets, and Naruto has to figure out how to unlock them with the help of his newfound summoning ability.
One interesting plotline could be Naruto accidentally signing a harem contract and having to deal with the various female characters suddenly being very affectionate towards him. It creates a lot of comical situations as Naruto is usually oblivious to such things in the original series.
One interesting concept could be new types of summons. For example, instead of the common toads, snakes or slugs, there could be mythical creatures like phoenixes or griffins. This would change the dynamics of battles and alliances in the Naruto universe.
One interesting concept could be the unique combinations of summons. For example, a character might be able to summon both fire - based and water - based creatures simultaneously, leading to new and unexpected battle strategies. Another concept could be the origin and history of these multiple summoning contracts, perhaps they were created by an ancient shinobi who had mastered different elements.
One interesting story could be about a character who discovers a hidden power within the raven summoning contract. Maybe they find a way to summon a special type of raven that has unique abilities, like the power to see through illusions. This could lead to them helping their team in battles against powerful enemies.
One interesting plot could be a character discovers an ancient and forgotten summoning contract. This might lead to them summoning a powerful and unique creature that no one has seen before, changing the power dynamics in the Naruto world.
One idea could be a story where a young and inexperienced ninja discovers an ancient slug summoning contract. They initially struggle to communicate with the slugs but gradually form a deep bond. Maybe they use the slugs' unique abilities, like their healing powers, in unexpected ways during battles.
A common element is the discovery of the contract. It's often by accident, like Naruto finding it in a hidden place or during an adventure. Another element is the new abilities that come with the summons. For example, the summons might have special powers that Naruto can use to fight stronger enemies.
In some 'naruto cobra summoning contract fanfiction', there could be a story where the cobra summons are connected to an old prophecy. The protagonist, by signing the contract, is thrust into a journey to fulfill this prophecy. They might have to overcome internal and external obstacles, like dealing with other ninja clans who are jealous of their new power and also understanding the true meaning of the prophecy which is hidden in the cobra's lore.
There's also a fanfiction called 'The Forbidden Summoning Contract of Naruto'. Here, Naruto stumbles upon a summoning contract that was sealed away for a reason. The story dives deep into Naruto having to deal with the consequences of using this contract while also facing the threats from those who don't want him to have this power. It has a lot of action and some great character development.