One common theme is friendship. Their friendship often forms the basis of the story, whether it's a new friendship developing or an existing one being tested. Another theme is adventure. They usually go on some sort of journey or adventure together, facing different obstacles along the way.
A theme that can't be overlooked is cultural exchange. Given that they likely come from different cultural backgrounds (in the context of their original stories), in the fanfiction, there's often an exploration of how their different cultures interact and influence each other, which adds a really interesting layer to the relationship between leo and usagi.
Love is a very common theme. Since Usagi and Mamoru have a strong romantic connection in the original story, fanfictions often expand on their love, like how they overcome obstacles to be together.
One common theme is the clash and then the fusion of two different worlds. Harry comes from a world of wizards and magic, while Usagi is from a world of sailor senshi and lunar powers. Fanfictions often explore how these two disparate worlds interact and combine.
Common themes include the power of love. In many fanfictions, their love is so strong that it can conquer all difficulties. There's also the theme of protection. Usagi is often depicted as protecting misaki from various threats, whether it's from jealous rivals or difficult situations. And the theme of acceptance is also prevalent, as they accept each other's flaws and grow together in their relationship.
One common theme could be the relationship development between Misaki and Usagi. It might explore how their bond grows over time.
One common theme is the 'forbidden love' aspect. Since Jadeite is often an antagonist in the Sailor Moon universe and Usagi is the protagonist, their relationship goes against the natural order, which makes for an interesting and often angsty story. Another theme could be 'redemption'. Jadeite might be shown as trying to redeem himself through his relationship with Usagi.
One common theme is the blending of different power systems. Goku has his Saiyan powers and Usagi has her Sailor Moon powers. Fanfictions often explore how these powers interact when they are married. For example, they might combine their powers to defeat a powerful villain. Another theme is the cultural clash. Goku comes from a more action - based, martial - arts - focused world, while Usagi is from a more magical girl - type world. How they bridge these differences in their married life is often explored.
One of the typical themes is the contrast between their personalities. Haruka is often seen as more cool and aloof while Usagi is bubbly. Fanfictions play with how these different personalities interact. Also, the theme of protecting each other is quite common, especially in stories where they face threats together.
One common theme could be the exploration of their relationship, whether it's a deep friendship or something more. Another might be their adventures together in different settings.
One common theme is the exploration of their different worlds. Draco from the Harry Potter universe and Usagi from Sailor Moon have very distinct magical worlds, and fanfictions often play with how they interact.
A theme that frequently appears is the power of their connection. Their combined powers or just their emotional connection can be a big part of the story. Also, there's the theme of acceptance. They accept each other's flaws and grow together. In some fanfictions, they face challenges that test their relationship, but in the end, acceptance prevails.