One way is to use the character abilities from the game. For example, if there's a special jutsu in the Naruto game, you can have your fanfic characters use it in unique situations. Another way is to borrow the game's leveling system. Maybe your fanfic character starts at a low level and has to train to gain new powers like in the game.
One of the most used game elements is the summonings. In the Naruto games, characters can summon various animals. In fanfiction, you can create interesting scenarios where characters summon unexpected or powerful creatures. Another great element is the transformation jutsus. These can be used to create plot twists or for characters to gain an edge in battles.
One way to combine these elements in a fanfiction could be to have Naruto characters in the world of Game of Thrones. For example, Naruto with his ninja skills could be like a mysterious warrior in Westeros. The harem aspect could be added by having multiple female characters, like from both Naruto and Game of Thrones universes, being attracted to this new character. Maybe Naruto's kind heart and his power make him stand out, and the female characters, such as Sansa Stark or Sakura, form a sort of harem around him.
Even characters from other villages could potentially be allies. For example, Gaara. In the game world, he and Naruto could form a powerful duo, with Gaara's sand - based attacks complementing Naruto's Rasengan - like moves. They could fight together against common in - game threats.
In Naruto fanfiction, the five elements (fire, water, earth, wind, and lightning) are often incorporated in various ways. For example, a character might have a unique jutsu that combines different elements in a new and powerful way. Some fanfictions might explore how a character with an affinity for one element could learn to control another element through intense training or a special encounter. Another common way is to create new clans or groups that have a special connection to one or more of the five elements.
Naruto in the Game of Thrones universe might struggle with the moral ambiguity that exists there. In his own world, he has clear ideas of good and evil, but in Westeros, things are not so black and white. He may try to introduce his values of friendship and loyalty, which could either be embraced or rejected by the inhabitants of this new world.
Maybe in the fanfiction, Naruto is in a game where the rules are based on different ninja clans' techniques. So he has to learn and adapt to new ways of using his chakra and jutsu. He could start as a low - level character in the game and level up by defeating bosses that are actually replicas of powerful shinobi from the Naruto universe. This would give him the opportunity to explore different aspects of his own powers as well.
If Naruto was a Lannister in a Game of Thrones fanfiction, he'd be a very different kind of Lannister. He'd probably use his ninja skills to protect the family in ways they've never seen before. Instead of the usual backstabbing, he might bring in a sense of loyalty and honor that the Lannisters lack. He could use his jutsu to make the Lannister stronghold more secure, like creating barriers with his earth - style jutsu.
A possible plot could involve a great threat that requires the combined forces of both worlds. Magic from both universes might be the key to defeating this threat. The Targaryens' dragons could be compared to some of the powerful beasts in Naruto. And the idea of the Iron Throne could be something that Naruto characters might not understand at first, but as they get involved in the politics of Westeros, they start to see the importance of power and control. This fanfiction would be full of adventure, political drama and magical battles.
I'm not entirely sure as 'lemon' in fanfiction often implies some inappropriate or romantic/adult - themed content. But generally in Naruto fanfiction, it could be about creating new storylines within the Naruto universe, perhaps with original characters interacting with the well - known Naruto characters.