Without going into much needless detail:
during their latest adventure (see The Clue at Cackle Creek, Summer fans!) four kids (cough 17-old-ish in this story) managed to get their hands on an amazing artifact.
It was called the Bewitchery Diamond, and it was a palm-sized gem that could change your story if you made a wish on it. Its limitations were unknown, but the children have successfully used it in the past to: change their genders, swap their bodies, grow to tiny or enormous sizes; (yep this thing is the ultimate fetish tool :p...)
However, this power came at a cost. First: you could never be certain exactly how the wish came true; some outcomes, as the children learned, could be quite horrific. Second, nobody not even the person using the diamond could be sure that they'd remember the change afterwards or notice that it has happened in the first place. These two conditions made the diamond very dangerous to use, and indeed the kids have agreed among themselves to never use it again except in the case of a serious emergency.
But that was then. And that adventure seemed to be quite a long way away, as the four sat in front of the fireplace, chatting on a cold winter evening.
With the world cold and dark outside, and the four huddled together in the company of warm cocoa, and -naturally- reminiscing about their previous adventures, the talk quickly turned to the diamond.
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"Can you imagine what you could do with it?" Chris Clove daydreamed loudly. "I wouldn't have to be Ignored Chris anymore - I could be Chris Clove, the...school's superstar!"
"If I could use it I'd ask to grow up right now. Being the youngest sucks." Mouse Salt (whose parents introduced new curfew rules just the other day) commented.
"Nonono, you guys are thinking about it all wrong!" Summer, the level-headed one, interrupted. "We should do something important and useful, like...I don't know...Use it against one of the bad guys we've been fighting in the past."
"What'd you wish for, Jamie?" Chris asked their fourth, oddly silent friend.
"Oh! ...me? I don't know, I guess I never thought about it."
"It's not like you to be so boring" Chris joked.
But secretly all four were fantasizing about what they'd do with the diamond that night, and at one point, one of them could not stand it anymore and tiptoed back to the living room, took the diamond out of its hiding place and said the words...