Perhaps the ANBU has a personal vendetta against someone in Konoha who is too powerful to take on while remaining in the village. Leaving Konoha gives them the freedom to train and gather allies to come back and face their enemy. They might leave secretly, under the guise of a mission, and start building their strength in the outside world, all while Konoha is left in the dark about their true intentions.
It could be Kakashi. He has a complex past and has been part of the ANBU. Given his experiences, he might have a reason to leave Konoha. Maybe he discovers something about the Sharingan or the Uchiha massacre that makes him question the village's integrity. He's a popular and well - developed character, so a story about him leaving as an ANBU would be interesting.
In this type of fanfiction, Naruto leaving Team 7 can be a very emotional and plot - twisting scenario. It might lead to Hinata stepping up to support Naruto in different ways. For example, she could be the one to convince him to come back to the team eventually. Also, this situation can explore the deeper feelings between Naruto and Hinata as they are forced to deal with the change in their dynamic.
One possibility is that Naruto is on a quest for self - discovery. Leaving the village to find the Sage gives him a chance to be away from the familiar and face new challenges alone. He might encounter different types of enemies and allies during this journey. This could also be a way for him to prove himself not just to the village but also to himself. He wants to show that he can grow and become stronger without always relying on the village's resources.
The title 'When leaves fall' in a Naruto fanfic could suggest a time of transition or reflection for the characters. It might involve a plot twist or a character's growth during this season.
Naruto might initially be in denial. He's so used to having Sakura around and believing that they have a future together. So when she leaves for Sasuke, he might think it's just a temporary thing or that she's been influenced by something or someone. But as time passes and he realizes it's real, he would be deeply hurt. He might also start to question his own self - worth, thinking that he wasn't good enough for Sakura. And he might even try to win her back at first, but then slowly come to accept the situation and focus on his other responsibilities like being a ninja and protecting the village.
In some fanfictions, Naruto might leave the Anbu due to internal conflicts within the organization. There could be corruption or power struggles. Naruto, being the idealistic character he is, would not want to be part of such a messed - up system. He might have discovered some dark secrets about the Anbu that made him decide it was not the place for him.
Naruto would probably be shocked at first. He might not have expected Hinata to leave him for Kiba. He could be angry at himself for not noticing Hinata's unhappiness sooner.
He might meet other wandering ninjas who are also on a quest for power or knowledge. They could either become his allies or foes depending on their motives.
Naruto could encounter wandering ninjas who have their own stories and reasons for not being part of a village. Some might be outcasts due to their beliefs or powers, and Naruto's interaction with them could lead to either conflict or new friendships. He may also come across some of the shinobi who fought on the opposite side during the war but now have different outlooks on life. Through these meetings, Naruto gets a broader perspective on the ninja world.