This is C.
We need to figure out who is doing what when before we do much more.

I've spent quite a while thinking, and I finally think I have a good plan. Everything I did had a reason. Such as, no one could decide who is going to join Pitch and Chaos, and who would fall in love with Chaos.
I went through and picked out what I'd seen from the other Brainstorms was supposedly going to be dealt with by each one of us. Family associations, the losses of loved ones, etc. Those who were left, I chose for the three remaining roles.

The main roles/ties for each one of us:

Sierra/Lili- Chaos falls in love with her
Fawn- Protector's daughter
Destiny- she just has a bunch of trouble with her powers
Caia- her best friend, who's dead, is revisited thanks to Tigerlilly
Tigerlilly- Tsar Lunar (the Man in the Moon)'s great-granddaughter
Willow- Pitch has convinced her that the Protectors might have her father, who she thinks is dead
Ember- Pitch's great-granddaughter
Bella- Joins Pitch and Chaos (temporarily)
Crystal- Joins Pitch and Chaos (temporarily)
Kit- Chaos's little sister

I'm hoping that you understand what I meant now.

More specifically, what (from what I've seen) the different things each person need to do are:

Sierra/Lili- Slowly open up to someone.
Learn about powers and center. Because I'm so shy, I'm planning on having the Protector himself work with me on that.
There's this phrase I love: "If I only know one side of the story, I'll chase the monster through the forest. If I know them both, I'll invite him in for tea." I think that, using that philosophy, C might be nice to Chaos. Because of that, I guess I can twist it so they end up falling in love. I personally really want Chaos to end up being a good guy. Ya know, in the 'final battle', he ends up changing sides cause of his little sis and maybe me and stuff. I want you guys' opinion on that, though.
Also, I was thinking that I could go on that quest with Caia. If that's okay with her.

Fawn- The Protector is her dad. That just screams family drama to me. Plus I'm sure there'll be some accusations tossed around about him being impartial to her, which will bring MORE drama. Ah. Teenagers.
Fall in love with one of the guys.
Go on that quest with Tigerlilly, I think you chose.
You try to find your powers and your center. I can imagine that being a whole lot harder with the Protector as your dad. Y'know, 'this should come easy, and it's not' kinda stuff.

Destiny- You have, like, no family whatsoever. So... I figured that your powers would probably be the biggest thing for you.
Pitch could give you nightmares about being alone and everything, and you could be hesitant to trust anyone.
Then of course, along comes your quest. Might I suggest you go with Kit?
You fall in love with one of the guys(?).
You find your center.

Caia- You go with Tigerlilly to see your friend in the book and see Pitch.
You fall in love with one of the guys(?).
You go on a quest. (With me?)
Learn your powers and your center. Maybe on the quest?

Tigerlilly- Take Caia to see her friend.
Do the whole Pokemon thing.
Family drama with the Man in the Moon.
Go on that quest into a book with Fawn.
Discover your center.

Willow- You distrust the Protectors and look for your father at every turn.
You fall in love with one of the guys(?).
You go on the quest with someone (I suggest Ember).
You try to find your center, which I think would be a struggle with so much distrust. I think it would be really cool if you were to discover it while on your quest.

Ember- You already know your powers and center, so I'm guessing you would just be in a constant battle against Pitch and your emotions.

Bella- Ok, someone needs to befriend Bella to show she's not just a bully.
And then of course she'll be traded to Pitch and Chaos for an undecided reason.
I personally think that you should discover your powers (and center) while with Pitch, but that's up to you.

Crystal- You've got drama because of your brother, and that needs to show... somewhere.
Trade yourself to Pitch and Chaos... for an undecided reason.
You've been super sweet and kind, and I think that'd be great to keep up.
You need to find your powers and your center. I advise that you do that either before joining Pitch, or after you're freed.

Kit- You've kinda befriended C, and that is something that I'm kinda hoping you'll continue to do. (I'm planning on opening up to either you and/or Crystal, but it'll take some patience on your character's part)
Write something super dramatic with finding out that Chaos is your brother. You can start trying to convince him to stop helping Pitch, you can simply be nice to him, or you can hate him unconditionally. Up to you.
You also need to learn more about your powers, learn to control them, and find your center. My idea would be that the Protector works with you on controlling your powers, but then on the quest, when it's vital for them to be used right, you mess up. Just an idea.
I think you said you wanted to fall in love with one of the guys.
I also thought that it could be entertaining for you to play a form of a middle man in whatever relationship is formed between Chaos and C. I dunno, just an idea.

For a timeline of events-
The journal trip (Tigerlilly & Caia)
Pokemon
Training with the Protector (mainly C & Kit, but everyone a little)
Family drama (Fawn & Protector, Tigerlilly & MiM, Kit & Chaos, Ember & Pitch, Crystal & brother)
The Protector is kidnapped
Trade Crystal & Bella for the Protector
Go on quests
Meet boys
Lots of drama and fluff for a while
Big battle

Okay, well there's an idea for why the girls join Pitch and Chaos.

What do you think? Will that work? Cuz using that, everyone can be on the same page and the book will go a lot smoother.