"...Mami, that's not the end of it. I wish it was."
She looks back at you, trembling, "...what? What else could..."
You take a deep breath, "Mami, I earlier mentioned that we are overwhelmed by Corruption if our Soul Gem becomes filled. Corruption is the essence of human suffering...Grief incarnate. As our Soul Gems grow darker, they are immersed in the stuff of nightmares...and we begin to despair. Cleansing reverses the process, allowing us to free ourselves from that Grief, but if we don't cleanse...we fall into the depths, and lose ourselves to a madness born of pure suffering. We turn inward, casting aside our fading humanity and cursing the cruel world with all of our might...at that point, we can no longer be called Magical Girls. Do you understand?"
Her eyes are shadowed as her head hangs limp. For a moment, there is no movement...then, she shakes her head. Again. Again. You can practically see the dots connecting in her head.
When she makes eye contact, it is not the gaze of a human being, but something...simpler, more primal. The essence of horror, written upon a canvass of human features.
"...no...nonononoNO....we...we...we're...IIIEEEEEEEEEEEEEEEEEE!!!"
The noise that rips from her throat isn't something that can be produced by the human body, and, for a moment, the world seems to quake around you...and then it stills.
She breaths, looking at you, "We're Witches...or, Witches are Magical Girls. Maybe we're not there yet, but someday...this is why you asked. I can choose us, or I can choose them...the humans. My friends, or the world. I understand."
Slowly, she stands, dragging herself to her feet. She pulls out a Grief Seed, cleansing wordlessly...blackness billows out, and her black gem loses all color.
She stares at it for a moment, before laughing, "HaHAhahahah! It's just decoration...just a lie, to hide what we really are! Look! Look at it! LOOK AT ME!"
She holds her Soul Gem out, and you and Kyouko lean forward hesitantly.
In the heart of her Soul Gem...a small metal cage. Not quite a Grief Seed...but far closer to one than a Soul Gem.
Mami lets go, and your hands instinctively snap out to catch her Soul.
Madness...madness, pure and all consuming, floods from it. Your vision blurs, and there's a hand on your shoulder.
"Stay strong, Homura."
Your beloved's voice gives you strength, and a will of iron clamps down, crushing the swirling insanity before it can consume you.
Mami collapses like a doll with her strings cut. You cradle her Soul, while Kyouko catches her body.
Eyes of flame meet your own, "She's...is she going to be okay, Ribbons?"
You shake your head, the sound of ratcheting clockwork accompanying the motion as you body shifts, "...not today. Not tomorrow. Maybe someday. For now...we can be there for her. I don't know how she'll be when she comes back...hopefully better than before, but..."
Tears drip from Kyouko's eyes, scorching the tiles of the bathroom floor.
...To be continued.