Renfield isn't derived from a comic. It's likely to have been created from an original concept or adapted from another form of media.
One idea could be exploring Renfield's past before he became Dracula's servant. Maybe he was a normal man with a family and a job, and then something tragic happened that led him to Dracula. Another could be a story where Renfield tries to break free from Dracula's control on his own, without the help of the vampire hunters. It could show his internal struggle between his loyalty to Dracula, which has been forced upon him, and his own will to be free.
To start writing Renfield fanfiction, begin with a strong opening scene. Maybe it's Renfield in the middle of one of his strange acts in Dracula's lair. This will immediately draw the reader in. Next, think about the tone you want for your story. Do you want it to be dark and spooky like the original, or more light - hearted? Then, start building the plot. You can base it on Renfield's desires, like his craving for life - force or his loyalty to Dracula, and then twist it in new directions.
No, Badlands isn't based on a comic. It's an original creation.
Yes, Kingsman is based on a comic series called 'The Secret Service'.
No, it isn't. 'The Protector' has an original story that wasn't adapted from a comic.
Yes, it was. Unbreakable was indeed based on a comic.
Sure is. Shazam is rooted in DC Comics. The comic provided the foundation for the character's traits, powers, and adventures that we see in various adaptations.
It is indeed based on a comic. The creators drew inspiration from the comic's unique plot and visual style to bring Red to life on the screen. Some elements might have been slightly modified for the adaptation, but the core concepts remained intact.
Definitely. The Sandman was originally a comic that gained a huge following before being adapted for other media. The adaptation tries to stay true to the core concepts and characters from the comics.
Yes, it is. 'The Gifted' is indeed based on a comic.