Cassie is one of those writers who started out with fanfiction (or fandom) and moved on to original fiction. What is fanfiction? Fanfiction is fiction written in another story's (writer's) settings but the plot is original. Some use same characters, some add their own; some maintain the personalities, some change them to fit their plot; some use the same timeline, some move the story a few (hundred) years back or forth. Since the author has rights for his/her work, fans do not earn any money from their fiction. They're just doing it for fun (their own and also others' - we have come so far that fans also have fans).
The most popular fanfiction subject is 'Harry Potter'. Thousands and thousands (maybe even millions) of stories are based on JK Rowling's stories. For such a long period of time the Harry Potter stories were WIP or work in progress and therefore provided quite some time for speculation or 'retelling the story', changing the past, recreating situations the fans didn't like. The last option created AU's or alternate universes where the fan could change more of the story than when writing relatively canon (sticking close to the original). Now, as the author's storytelling has come to an end, the fans can continue where the author left off.
Clare wrote a trilogy, The Draco Trilogy (Draco Dormiens, Draco Sinister, Draco Veritas. Here an excerpt from the beginning of the story, explaining everything:
Disclaimer: This story is based on characters and situations created and owned by JK Rowling, various publishers including but not limited to Bloomsbury Books, Scholastic Books and Raincoast Books, and Warner Bros., Inc. No money is being made and no copyright or trademark infringement is intended. This work contains quotes from movies and television shows, stories and plays, novels and films. They are cited at the end of each chapter. Other citations can be made where necessary. I collect funny quotes, like a pack rat, and don't always know where they come from. Sometimes I make source errors in good faith, or leave things off by accident. Sometimes I don't know where something comes from, in which case I note it anyway. Let me know any of these things, and I will add the citation.Cassie did indeed use a lot of quotes and scenes from others and there was a huge discussion around this 'plagiarism'. This, and her starting her own writing career, were the reasons the trilogy is no longer available online. Most have the stories downloaded to their computer from ancient times... but I think if you search really hard, you'll find someone/somewhere from whom/where you can get them...
Author's Notes: This fanfiction is an AU: Alternate Universe. It was written in the year following Goblet of Fire and does not incorporate material from OOTP, HBP or JK Rowling's fansite, all of which post-date it. It posits a universe in which Sirius is still alive, and so is Dumbledore; Fudge remains Minister of Magic, Luna Lovegood does not exist, Blaise Zabini is a girl, Ginny's full name is Virginia, and so on.
But she also added her own 'things': the Magid classification (really powerful wizards among mediocre wizards, you have to be born as one), certain objects (Draco's Epicyclical Charm for example) and spells, HMS Harmony/Dramione ships (the first is Harry/Hermione, the second Draco/Hermione) (shipping means who ends up falling in love and such, so a H/Hr shipper would write a story where Harry and Hermione fall in love) and so on. The story is well written for fanfiction (she is a real writer now, as opposed to many who simply write) with the good grammar (lack of spelling mistakes) and I personally really enjoyed the usage of other quotes (especially ones from Buffy, since I'm a huge fan of that, too). Even though it was good, it's still fanfiction.
Her own stories, though, are a slightly different story. Her genres are urban fantasy and YA literature. Meaning, she writes fantasy novels set in modern world for teens. She has created her characters' a whole parallel universe (things regular human beings can not see...). The Shadowhunters and the Downworlders being the fantastical element here. Currently two out of three in the Mortal Instruments trilogy have been published (City of Bones, City of Ashes; City of Glass) but you can read the first chapter of the third book online, a little peak. Also you can see the titles of the chapters.
She pretty much created something really-really new and her own (like the power runes) and developed it. What I mean is, she didn't get her characters from mythology. In a way, that's a good thing (something new!) but it's also really fun to read some new interpretation of something old.
Also, there's the typical 'you fall in love with the one who you hate at first' but there's an added twist: they turn out to be related! But I've a feeling something's going to change in book 3. There's also the best friend who doesn't really fit into the new world (with your new friends) but who tries anyway (and they get much closer through this experience...) and eventually gets himself turned into a vampire (who, with some help from Jace's blood, can walk in the daylight) but still isn't quite it.
And there's the gay characters! Alec and Magnus, the warlock. They're absolutely amazing (it's great fun when Alec gets a fearless rune and then starts telling the parents that he's gay :D)! And the "How to come out to your parents" pamphlet that Luke/Clary gave Simon so he could get some help with telling his mum that he's a vampire... :D I think I can get a quote, it's fantastic:
"What's that you're holding?" he asked, noticing the pamphlet, still rolled up in her left hand.This was from City of Ashes.
"Oh, this?" She held it up. "How to Come Out to Your Parents."
He widened his eyes. "Something you want to tell me?"
"It's not for me. It's for you." She handed it to him.
"I don't have to come out to my mother," said Simon. "She already thinks I'm gay because I'm not interested in sports and I haven't had a serious girlfriend yet. Not that she knows about, anyway."
"But you have to come out as a vampire," Clary pointed out. "Luke thought maybe you could, you know, use one of the suggested speeches in the pamphlet, except use the word 'undead' instead of—"
"I get it, I get it." Simon spread the pamphlet open. "Here, I'll practice on you." He cleared his throat. "Mom. I have something to tell you. I'm undead. Now, I know you may have some preconceived notions about the undead. I know you may not be comfortable with the idea of me being undead. But I'm here to tell you that the undead are just like you and me." Simon paused. "Well, okay. Possibly more like me than you."
"SIMON."
"All right, all right." He went on. "The first thing you need to understand is that I'm the same person I always was. Being undead isn't the most important thing about me. It's just part of who I am. The second thing you should know is that it isn't a choice. I was born this way." Simon squinted at her over the pamphlet. "Sorry, reborn this way."
Clary sighed. "You're not trying."
"At least I can tell her you buried me in a Jewish cemetery," Simon said, abandoning the pamphlet.
I consider her my idol for she uses/writes (the terms) 'urban fantasy' and YA (the latter being used by their whole writing group, though I'm sure there are others) that have inspired me quite a lot (those being the genres I'd really like to cultivate myself). She's a simple girl who likes to write and that gives me hope. I can do that!
Either way, her stories are great fun to read and I can relate to them. Well, some parts of the stories. :D The relating part is what makes YA literature so much more fun to read than stories involving adults. Can't wait for the end of the series...