Kirito is more of a traditional swordsman in terms of his combat style. He often relies on his sword - fighting skills and his ability to quickly analyze his opponents. Yuuki, on the other hand, has a very unique and flashy fighting style. Her movements are more acrobatic.
In my opinion, Kirito and Asuna could potentially win. Kirito has his dual - wielding skills and Asuna is no slouch either. They have fought against powerful bosses in SAO. Naruto is strong, but he might be caught off - guard by their speed and teamwork. Kirito and Asuna have a lot of experience fighting together and could coordinate their attacks well. If they can quickly close the distance and take Naruto out before he can use his more powerful ninjutsu, they could be victorious.
In my opinion, Kirito might have a bit of an edge. He has fought in more diverse situations and has a broader range of combat techniques. However, Eugeo's deep understanding of his own world and its rules gives him a strong base. So, while Kirito may seem more likely to win, Eugeo could definitely surprise him.
One common theme is friendship. Their relationship is often explored in depth, showing how they support and care for each other. Another theme is redemption. Ash's past and his journey towards a better self is often a part of the story.
One common theme is friendship. Their strong bond as friends is often explored. For example, in many fanfics, they support each other through tough times.
One common theme is loyalty. Their unwavering loyalty to each other is often explored, whether it's in the face of danger or personal struggles. Another is self - discovery, as they both grow and learn more about themselves through their relationship.
One common theme is friendship. Their relationship often starts as a deep friendship that has the potential to develop into something more. Another theme is sacrifice. They are often willing to sacrifice for each other in these fanfics. Also, the theme of redemption can be seen, as they help each other find a better version of themselves.
I'm not sure there are many specific fanfics just on this one aspect. However, you could start by looking on fanfic platforms like Archive of Our Own. Search for 'Banana Fish Eiji kidnapped' and you might find some relevant works. Some fanfics may explore different motives for the kidnapping, such as using Eiji to get to Ash or for some political gain within the complex world of Banana Fish.
In a fanfic, Eiji could get injured while exploring an abandoned building that has some connection to the Banana Fish mystery. Maybe he trips and falls, hitting his head. This could lead to a series of events where Ash has to take care of him, and in the process, their bond deepens as they share more personal stories while Eiji recovers.