The child could have Naruto's chakra control. This would allow them to perform powerful jutsus like the Rasengan. And with Mirajane's influence, they might also be able to use some form of transformation magic. For instance, they could transform into a powerful beast - like form similar to Mirajane's Satan Soul form but with a ninja - like twist.
Well, it could be a story full of adventure. Their child might inherit Naruto's determination and Mirajane's magic abilities. Maybe the child has to face some new threats in the ninja - magic world. For example, a new evil organization that combines ninja and dark magic skills. The child could use Naruto's shadow clone jutsu and Mirajane's take - over magic to fight against the bad guys.
In most Naruto fanfictions, Mirajane is from the Fairy Tail universe and Naruto is from the Naruto universe. They exist in different fictional worlds, so the idea of Mirajane 'cheating on' Naruto doesn't really make sense in the context of traditional fanfiction. However, if it's some kind of crossover fanfiction with a really strange and out - of - the - box plot, it would be very rare and not a common trope.
One possible fanfiction could be about Naruto visiting the Fairy Tail world and teaming up with Erza and Mirajane. They could go on a quest together to defeat a powerful dark wizard. Naruto's unique ninja skills would blend well with Erza's swordsmanship and Mirajane's takeover magic.
They could start by meeting in a strange, in - between world. Naruto is intrigued by Erza's armor and Mirajane's different forms. They soon realize they have a common goal, which is to find a way back to their own worlds. As they journey, they share stories of their past adventures, with Naruto talking about his battles in the Hidden Leaf Village and Erza and Mirajane sharing tales from Fairy Tail.
One possible fanfiction could be about Naruto ending up in the Fairy Tail world and teaming up with Erza and Mirajane. They could go on adventures together, with Naruto's unique ninja skills complementing the magic of Erza and Mirajane. For example, Naruto's shadow clone jutsu could be used in creative ways during battles against powerful foes in the Fairy Tail universe.
In a Naruto - Fairy Tail - Mirajane fanfiction, it could start with Mirajane traveling to the Naruto universe. She might be on a quest to find a special kind of magic that she believes exists there. When she arrives, she meets Naruto. Naruto, being the friendly and curious person he is, offers to help her. They then explore the ninja world together, with Mirajane learning about ninjutsu and Naruto learning about Fairy Tail magic.
One interesting aspect of Naruto, Mirajane and Lisanna fanfiction could be the crossovers. Writers might create a story where Naruto's ninja world collides with the Fairy Tail universe of Mirajane and Lisanna. They could have unique adventures together, perhaps facing a common enemy that combines the threats from both their worlds. For example, a dark sorcerer - ninja hybrid villain.
There are quite a few. You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Naruto Mirajane' and you'll find a variety of stories with different themes and plotlines.
One idea could be a crossover where Naruto, Erza, and Mirajane are brought together by a powerful magic spell that goes wrong. They have to work together to reverse the spell's effects while also dealing with the differences in their worlds. Naruto's ninja skills, Erza's swordsmanship and armor changing abilities, and Mirajane's demon form and magic could create really interesting interactions and battle scenes.