The main themes include cultural clash. Naruto's world has its own set of values and cultures, and Rukia's world is different. When they come together in the harem fanfiction, this clash of cultures can lead to interesting storylines. Love and jealousy are also key themes. With multiple characters vying for the attention of Naruto or Rukia, there is bound to be some jealousy, and at the same time, the exploration of different types of love.
Well, a common theme is friendship and loyalty. In these fanfictions, as the harem forms around Naruto and Rukia, the characters need to learn to be friends and be loyal to each other. Also, self - discovery is a big theme. The characters, especially those new to the harem situation, have to figure out their feelings and their place in this new group. There is also the theme of adventure, as they often go on quests or face challenges together.
One of the main themes is usually the development of relationships. Since it's a harem concept, it focuses on how Naruto and Rukia interact with the multiple characters in the harem. Another theme can be the adaptation of different worlds. Naruto and Rukia come from different anime universes, so the fanfiction often explores how their two worlds blend together.
Friendship across universes is also a popular theme. Naruto and Rukia come from different fictional universes, so the idea of them forming a strong bond despite their differences is often explored. They learn from each other's values and ways of life, like Naruto teaching Rukia about the importance of never giving up in the face of adversity, and Rukia showing Naruto the more spiritual side of things.
One common theme is the 'opposites attract' concept. Naruto is very energetic and loud, while Rukia is more reserved. Another theme could be about them overcoming differences between their two worlds. For example, Naruto's ninja world and Rukia's world of spirits.
In many 'naruto x rukia romance fanfiction' works, a significant theme is the power of love across different universes. Their love is often shown to be so strong that it can break down barriers between the ninja world and the world of spirits. Additionally, themes of sacrifice and loyalty in their relationship are also quite prevalent, as they would do anything to protect each other despite their different origins and abilities.
I'm not sure about all of them, but 'Naruto and Rukia: Harem Chronicles' could be a great start. It often plays with the idea of Naruto's charm and Rukia's unique personality attracting different characters into their circle. The story has some exciting plot twists and explores the concept of a harem in a creative way. There are also some fan - made websites where you can find more such fanfictions.
Naruto would probably be very curious about Rukia. He'd ask her a lot of questions about where she's from and what her powers are. Rukia, on the other hand, might be a bit guarded at first but would gradually warm up to Naruto's friendly nature.
Love is a major theme. Since the kiss implies a deep emotional connection between Ichigo and Rukia. Another theme could be sacrifice. In many of these fanfictions, they might be willing to sacrifice for each other, which leads to that moment of intimacy.
Power dynamics can also be a theme. Naruto is a powerful ninja, and in these fanfictions, his power may influence how the relationships in the harem develop. Sometimes, the female characters are also strong in their own right, and the story shows how they interact with Naruto's power and each other's powers in the context of the harem and the ninja world.
Power - or the lack thereof - in relation to the harem is also a theme. Some fanfictions explore how Naruto's growing power affects his relationships. Does it attract more characters to his harem? Or does it create jealousy or fear among the harem members? This theme adds an interesting dynamic to the overall story.
Another theme is the exploration of the Naruto universe from a different angle. Since it's a harem fanfiction, it can show different sides of the characters and their interactions in a non - canon way. For example, how Naruto's new relationships might change his goals or how the female characters interact with each other because of their shared feelings for Naruto.
A common theme is friendship evolving into something more. Their initial respect for each other as comrades in Soul Society often develops into deeper emotional bonds in fanfictions.