Next book on the horizon

I think I've decided to start writing my next book after my Halloween party this year.

I'm making no promises about starting immediately on Sunday or anything (although I might), but I really want to start writing this. It is not going to be a NaNo novel. It is not going to be a thing I rush to get done at all costs, though if I write at my usual pace it'll come out pretty damn fast. I have a vague goal of finishing it by the end of the year, but I'm not going to sacrifice quality if I just can't do it.

Stuff I know about the book so far:

• It is a contemporary YA book with very slight magical realism flavor.
• The protagonist's name is Megan.
• Megan is asexual and homoromantic. She doesn't know that at the beginning of the book.
• Megan is a very serious artist. She likes to draw cities and buildings and inanimate objects, and prefers to draw in ink.
• Megan is a senior in high school.
• She is trying to get into art school based on the enthusiastic reception of some of her drawings at a show.
• Megan lives with her older sister Dyane.
• Megan is on the tall side of average, heavyset and curvy, half Hispanic/half white, and has brown hair and brown eyes. She doesn't have much hair actually--it's buzzed to peach fuzz. She has pierced ears and a pierced nose.

Dollmaker utilities only have one body type usually. Bah.

• Megan sits behind a boy named Brady in homeroom. Brady is important.
• Brady is attracted to Megan. Megan is not attracted to him.
• Megan doesn't talk very much and is externally kind of intimidating. That's on purpose.
• Megan's sister Dyane is an aspiring actress and has a serious boyfriend. Megan has a loving but sort of disconnected relationship with her sister.
• Megan had some very bad experiences with boys when she was in middle school because she hit puberty early. When she learns about asexuality, she struggles to decide whether it describes her or whether her bad experiences explain her lack of interest.
• Megan joins a GSA during the course of the book and dates a girl for some of the time in the book.
• Megan's drawings operate on specific rules and go in a certain order that she feels conflicted about breaking when she's called to diversify her portfolio.
• Megan sees a school counselor about several things in the book. The counselor is a man, and he's not useless.
• Even though Megan learns she is an ace lesbian in the book, her most important relationship in the story is a friendship.

Stuff I don't know yet:

• A title. But for now I'm tagging my posts "ace of arts" because that's funny.
• What the deal is with Megan's parents.
• Megan's last name.
• The exact circumstances of her crisis with getting into art school. 
• Megan's girlfriend's name and what her "deal" is, except in my head she's kind of a jerk and probably has cool hair that's at least two colors.
• How exactly Megan's voice will come off in the book.
• How exactly the sorta-magical-realism bit will go, though I suspect it will feel a little like lucid dreaming.

I'm excited to get started, but also worried it will fall on its face and just turn into a ramble-fest that eclipses the plot.

So, you know, the same thing I feel before starting every book. ;)