To start writing Romantic Killer fanfiction, begin by choosing a character or a relationship you want to focus on. It could be the main character's journey or a side character's story. Next, think about what kind of plot would be exciting. Maybe it's a mystery that the characters have to solve or a romantic misunderstanding that needs to be cleared up. You can also look at other fanfictions for inspiration, but make sure to add your own unique touch.
Well, start with a strong concept. For example, you could think about what if a certain event in 'Romantic Killer' had a different outcome. Then, plan out your story structure a bit. Decide on the beginning, middle, and end. But don't be too rigid, as the story might evolve as you write. When it comes to writing, use vivid descriptions to bring the 'Romantic Killer' world to life. Describe the characters' emotions and the settings in detail so that readers can really immerse themselves in your fanfiction.