Another theme is cultural exchange. Goku is from a more action - oriented, martial - arts - based culture in Dragon Ball, while Usagi is from a magical girl anime with a different set of values. Fanfictions may play with how they introduce their respective cultures to each other.
Another theme is the culture clash. Goku comes from a martial - arts - focused, somewhat simple - living world in Dragon Ball, while Usagi is from a more magical and girly world in Sailor Moon. Fanfictions play with this difference, like when they first meet and don't understand each other's ways of doing things. It can lead to some really funny and also some really touching moments as they learn about each other.
Yes, Archive of Our Own (AO3) is also a great source. You can search for 'usagi x goku' and get a bunch of results. Some fanfictions might focus on their friendship and how they could learn from each other's skills and strengths. For example, Goku's martial arts skills and Usagi's leadership and magical abilities could be combined in interesting storylines.
There's also 'Goku and Usagi's Adventure' which is quite popular. In this fanfiction, the author focuses on the relationship development between Goku and Usagi. It starts with their initial encounter which is full of misunderstandings due to their different cultures, but as the story progresses, they start to understand and respect each other more, and it leads to a really heartwarming adventure together.
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.
There's also a fanfiction titled 'Goku - Usagi: United Worlds'. It starts with an unexpected encounter between Goku and Usagi, which leads to them falling in love and getting married. The story delves into how their different friends and families from their respective series react to their union. It's interesting to see how the Dragon Ball characters interact with the Sailor Moon characters in this fictional scenario.
Some fanfiction communities might have threads dedicated to this pairing and lemon fanfics. You could join those communities and ask for recommendations. People there are often very helpful and can point you to some great misaki x usagi lemon fanfictions.
Lemon fanfiction often involves a certain level of romantic or spicy elements. In misaki x usagi lemon fanfiction, it might explore their relationship in a more intense and passionate way. Maybe it shows their deep emotional connection and physical attraction, with detailed descriptions of their interactions.
There's also 'When Ranma Met Usagi'. This one focuses a lot on the cultural differences between their two worlds. It shows how they overcome those differences and gradually fall in love. The descriptions of the settings, whether it's Ranma's martial arts world or Usagi's magical girl realm, are very vivid and immersive.
Tuxedo Mask could also be in the harem. He has a long - standing relationship with Usagi, and in a harem scenario, his feelings for her could be even more intense, competing with others for her love.