Target market: Me.

I mean, no one else wants to read this crap.

If I were writing a serious novel, though, I'd follow my own advice: Pick a person, preferably someone that you like. Write the story for that person, like you're giving him or her a gift. That's your target audience.

Hey, it worked for Tolkien and Carroll, among others.

People who share demographics with that person may like it too, and so you might have to tell the publisher that it's for little old ladies, not "Aunt Carol." But that's okay.