One common theme is the complex love triangle. Since all three characters have their own feelings and histories, the fanfics often explore how they deal with their emotions towards each other. Another theme could be their shared adventures and how their relationships develop during those experiences.
Sure. You can try looking on fanfiction.net. There are often many works about different character pairings there, and you might find some great kagura x makoto fanfic.
There are many 'erza x jellal x kagura fanfic' out there. You can start by looking on popular fanfic websites like FanFiction.net or Archive of Our Own. Just search for the relevant tags and you might find some interesting ones that explore the relationships between these characters in different ways.
The character of Kagura in a reincarnated fanfic can be developed through her relationships. She could form new friendships with characters from different clans. This would force her to learn about different cultures and values, which in turn would shape her character. She might also have a romantic interest in a character, and this relationship could show her vulnerable side and how she grows through love and loss.
Kagura might interact with Sakura. Sakura, being a strong - willed and intelligent kunoichi, could offer her medical expertise to Kagura if she returned injured. Or they could have a girl - to - girl talk about their respective journeys in the ninja world.
The plot might involve the male reader suspecting the girl of cheating. He could start noticing little things like her being secretive about where she goes or who she's with. As he digs deeper, he finds out she's been making deals with the enemy or flirting with other guys for some advantage. This could then cause a big rift between them and the male reader would have to figure out how to deal with this betrayal.
Kagura was one of the main characters in Silver Soul. He was a very interesting and energetic character. The following are some of Kagura's classic sayings:
The world is full of opportunities, as long as you dare to think, you can do it.
There was no such thing as failure. It was just a temporary pause in success.
Living is not for others but for yourself.
In this world, only the living can see the truth of things.
What matters is not the result but the effort in the process.
If you feel pain, give up, because you have tried your best.
Everyone has potential energy, but it is easily covered by habits, blurred by time, and worn down by laziness.
The furthest distance in the world is not the distance between life and death, but the second I just got online, you went offline.
To defeat the enemy, you must first defeat yourself.
The biggest waste of time in the world is doing meaningless things.
As far as I know, Kagura is still alive in the Boruto manga. The story hasn't depicted her death yet. Maybe there will be developments in future chapters, but for now, she's safe.