In the Naruto x harem fanfiction, Naruto is a badass because of his combination of raw strength, strategic thinking, and his heart of a hero. He's not afraid to go against the odds and always finds a way to come out on top for himself and his harem.
A common theme is Naruto's growth in power. As he becomes stronger, it often serves as a magnet for characters to be part of his harem. For example, in many such fanfics, after a major power - up, new characters start to show interest in him.
Well, the theme of transformation is quite common. The Akatsuki members in the harem fanfictions often transform due to Naruto's influence. They might change their views on the world, on Konoha, and on their own violent ways. Another theme is the struggle for acceptance. Naruto has to accept the Akatsuki members as they are in the harem context, and they in turn have to accept him and the changes he brings into their lives.
One common theme is the fish - out - of - water scenario. Naruto, coming from his own ninja - filled world, suddenly finds himself in an elven world with different rules, cultures and magic systems. Another theme is the building of relationships within the harem. Each elf in the harem has her own personality and Naruto has to navigate his feelings for them. Also, adventure is a big theme as they often go on quests together, fighting enemies and exploring new places.
One common theme is redemption. Naruto, after being betrayed, often seeks to redeem himself or prove his worth in the eyes of others, especially the females in his harem. Another theme is trust. Since he was betrayed, rebuilding trust becomes crucial in his relationships with the harem members.
A common theme is the fish - out - of - water situation. Naruto, coming from his own ninja world, has to adapt to the KHR world. This creates a lot of humorous and interesting situations. For example, he might use his chakra in ways that are strange to the KHR characters. Another theme is the building of relationships. Since it's a harem fic, Naruto forms different kinds of relationships with multiple female characters, from friendship to something more romantic.
Naruto himself is always interesting. His unique personality and his journey from an outcast to a hero provide a lot of material for the fanfiction. His ability to form deep connections with the harem members despite his busy ninja life is a key aspect. Kin is also quite fascinating. Her own backstory and her relationship with Naruto can be explored in many different ways in the fanfiction, especially how she fits into the harem dynamic.
Some 'naruto x kin harem fanfiction' might focus on the power dynamics within the harem. Kin could be a central figure in the harem, and the stories could revolve around how she and the other members interact with Naruto in terms of power and influence. Maybe they train together and Naruto discovers new techniques through their combined efforts, which then helps him in his overall mission to protect the village.
One popular 'powerful naruto x harem fanfiction' is 'Naruto: The Harem King'. In this fanfic, Naruto is portrayed as extremely powerful and has a harem of various characters from the Naruto universe. The story often involves his adventures while dealing with the relationships in his harem.
In the Overlord world, Albedo could be one of the potential female characters. She is powerful and has a complex personality. In a harem fanfiction with Naruto, she might be intrigued by his different power system and his kind heart. Another could be Shalltear Bloodfallen. Her combat skills and beauty might make her interested in Naruto as well.