Should my character be a Tagalong Kid or an Old Maid?

The story is told through the eyes of a plucky female sidekick to a hero, who often provides comic relief, gets captured a lot, and plays the role of The Lancer in the hero's group...until she gets fed up with her role. Wanting to increase her competence and get The Hero of the group to notice her, she enrolls in an academy run by a mysterious headmistress known as The Authoress, who promises to turn any character into a Mary Sue.

Turns out, the academy is the Boarding School Of Hell. Painful physical procedures and dangerous drugs are used to alter the students' appearance, while brainwashing and Mind Rape are used to create new personae through which The Authoress can live vicariously. She decides to leave the school, but has to escape in secret. Once she escapes, she goes back to the group, and rallies them to launch an attack on the academy.

I'm not sure what the Plucky Female Sidekick should be like. I kinda have this idea that she'll either be younger than The Hero (he's early 20s and she's 16, so he sees her like a kid sister) or an Old Maid (he's early 20s and she's late 30s, so she's looked at to be a Cool Big Sis or Team Mom, but never taken seriously as an Action Girl or a Love Interest).

edited 22nd Dec '11 12:02:06 AM by LeighSabio

I know it's metafiction... but can you please try not to speak in tropes quite as much?

You're description of the plot works way better for a younger protagonist.