the_debt_of_time

Lily shook her head and laughed. "Let them have this surprise. They're slowly
weaning off the need to prank Filch and hex Slytherins. Speaking of hexes, I'm very proud
of you, Mia."
"Why's that?"
"Marlene," Lily replied.
"I can't believe McKinnon is in the Order," Mia hissed under her breath and looked
down at the end of the sofa where Sirius was aggressively rubbing her feet in what she
assumed was a pre-emptive attempt to avoid an argument about She-Who-Must-Not-Be-
Named.
"Well, I know how you feel about her, so I'm happy to see that you've matured and
are no longer letting your wand do all your talking for you," Lily insisted.
"I left my Tele-Portkey in my other robes," Mia said seriously, looking down at her
nails as though she were examining a fresh manicure. The pink polish that Mary applied a
week earlier was badly chipped. "Besides, was I going to hex the cow in front of
Dumbledore and a collection of Aurors?"
"No, she'll wait until she's sent on a mission and Marlene is her partner; then she'll
hex her good." Sirius chuckled, receiving an adoring smile from Mia in return.
"She would not," Lily argued. "Mia might have a grudge, but she would never risk
a mission for the Order."
"Actually... I'll be on a permanent mission outside of the Order," Mia slowly
explained, concealing her fading smile and the approaching scowl behind an expression of
indifference.
"What's that?" James rose a brow, looking anxious. "'Outside of the Order.' What
does that mean?"
Mia frowned, knowing that he was probably thinking that Dumbledore had
recruited her as a spy, thus putting her in danger. "I'll be fine. It's more behind-the-scenes
type of stuff: arithmancy equations, attempting predictions of future events," she lied
through her rehearsed excuses, "but it means I can't be at the meetings very often. If I'm
too involved there's a chance I could try to work the equations in favour of a predetermined
outcome, and that never works, so I have to get my information directly from
Dumbledore."