A key element would be the discovery of their relationship. It could be a shock to both of them and the reactions would be interesting to explore. Another element is how they interact with their shared friends and teammates. Do they keep it a secret or are they open about it? Also, their different powers could play a role. Maybe they combine their powers in unique ways to solve problems because of their new - found bond.
The exploration of their different heritages is important. Beast Boy is from Earth with his shape - shifting abilities related to Earth animals, while Miss Martian has Martian powers. How do these two different backgrounds mesh in a sibling relationship? Their upbringing also matters. If they were raised apart, how do they adjust to having a sibling now? And how do they handle any jealousy or competition that might arise? For example, if one is better at a certain skill than the other. This all adds depth to the fanfic.
In some fanfics, their sibling relationship could be explored through flashbacks. For example, showing how they were separated as children due to some intergalactic event. Then, in the present, they are reunited and have to catch up on all the years they missed. This could involve them learning about each other's cultures and dealing with the differences between being a Martian and a shape - shifter.
A theme that sometimes pops up is teamwork. Since they are part of a team in the original series, fanfics may focus on how they work together in different scenarios, highlighting their individual strengths and how they complement each other. Also, the theme of acceptance can be seen. For example, Beast Boy might have to accept Miss Martian's different cultural background or powers, and vice versa, which can create interesting storylines in fanfics.
You can start by looking on fanfiction platforms like Archive of Our Own (AO3). It has a large collection of fanfics for various fandoms, including Beast Boy and Miss Martian. Another option is FanFiction.net. Just search for the relevant tags and you'll likely find some interesting stories.
Character development is key. In a good 'Starfire x Beast Boy fanfic', we should see both characters grow. For example, Beast Boy might become more mature in his feelings for Starfire, and Starfire might understand Earth culture better through her relationship with him.
Friendship and teamwork are also common themes. Since they are from different universes, they have to work together. They learn to trust each other and overcome their differences. In many fanfics, they form a strong bond that helps them face various challenges, whether it's a powerful villain or a difficult situation in a strange new world.
One possible plot could be that they face challenges in protecting their unborn child from enemies who might want to use the baby's powers for evil. Since both are Martians, their child would likely have unique and powerful abilities that could attract unwanted attention.
A good non - lemon Beast Boy x Raven fanfic often has strong character development. For example, showing how Beast Boy's jovial nature can bring out Raven's more hidden emotions, and vice versa. It should also have an engaging plot. Maybe they go on a quest together and during that, their relationship deepens.
Well, in fanfics, Miss Martian and Superboy could have a very complex relationship. They are both powerful characters with different personalities. Their relationship could be based on mutual respect for their powers and the challenges they face. Maybe they start as friends who train together and gradually develop a deeper bond as they understand each other's backgrounds better. For example, Miss Martian's alien nature and Superboy's clone - origin could be points of connection as they both feel a bit out of place in the human world sometimes.
Perhaps the fanfic could explore the relationship between Miss Martian and the father of the child. It could show how they support each other through the pregnancy, and also how their relationship evolves. There might be moments of joy, worry, and discovery as they prepare to become parents.
In some fanfics, Miss Martian might teach Naruto about her alien culture and technology. This could be really fascinating as Naruto is always eager to learn new things. He could then use some of this knowledge to improve his own village. It's also interesting to see how the two characters from very different universes interact with each other's friends and allies.