Well, one interesting aspect could be his character development. He might start as one type of person and gradually change throughout the story of the light novel. Maybe he has unique relationships with other characters that add depth to the plot.
There is a fanfiction called 'Lucy in the Alternate Realm'. This one is interesting because it sends Lucy to an alternate realm where she has to find her way back. Along the way, she meets different versions of her friends and has to use her wits and magic to survive. It's a great read for any 'Fairy Tail' and Lucy fan.
Sure. There could be his family members. For example, his father or mother might play important roles in his life and in the story. Their influence on Paul can be a key aspect of his character development.
You can find 'Fairy Tail Lucy' fanfiction on FanFiction.net. There are tons of stories there written by fans all over the world. Just type in 'Fairy Tail Lucy' in the search bar and you'll get a long list of different fanfics to choose from.
There's not enough information to really know who Lucy specifically is. She could be just a regular reader of fanfiction who took the time to rate this piece as M. Maybe she's part of a fanfiction community where people rate works to help others know what to expect.
It could be inspired by her dreams. People often get creative ideas from their dreams. Lucy might have had some vivid and interesting dreams that she wants to expand on and turn into a novel. She could be exploring new worlds, characters, and storylines that came to her during sleep.
I'm not sure what type of Jereff and Lucy Doujinshi you're referring to. If you can provide more background information or context, I will try my best to answer your questions.
Other dragon slayers could be her potential allies. They might recognize her skills despite her being a princess. Also, magical creatures who are enemies of the dragons, like phoenixes or griffins, could side with her. And some wise old wizards or witches who see her potential might offer their help.