Ms. Fanservice: Complete with more than one scene where she conveniently goes dressless.
The Quiet One: Shares the position of character with least dialogue with Hitomi and Nagisa.
Story-Breaker Power: Pia was powerful enough to take on three monsters at the same time. Even by Seventh Magical Girl standards this is impressive. It's no surprise that Kyubey immediately tries to have her taken out of commission once she officially switched to the good girls' side.