I'm always up for ideas and teasers related to plot. XD Feel free to send it! I'm certainly interested, after all.
Okay. So. Iris Heart.
In the third game of the Hyperdimension Neptunia series, Neptune (the protagonist) gets tossed into an alternate dimension. There, she meets a different CPU (a sort of Goddess) of the nation of Planeptune. That's Plutia.

Plutia's a fluffy little sleepyhead who enjoys sewing up dolls, taking naps, spending time with her friends, and generally being almost as lazy as Neptune is. My own personal theory is that she's trying very, very hard to hide her true personality, though... because when Plutia gets mad, she activates her HDD form and becomes Iris Heart. It's kind of like Atma, but powered by people's faith instead of personal strength 'n stuff. And they're living deities.

Iris Heart is an extreme sadist who's traumatized at
least half the cast of the game, allies and enemies alike. She's so vicious, in fact, that she completely punked the Big Bad of the previous two games (sort of... it's complicated). She also tends to be the set-up for a lot of jokes, but ultimately she works pretty well within the series as a supporting protagonist, especially since the series has always been more about the characters and such than the major plotline. Plutia's very high on my list of favorite CPUs within the series, narrowly edged out by Rei (and sometimes Peashy, who's just flat-out funny).
Stick's got a thing for Iris Heart. o wo