"I'm not stupid!" Mikey laughed. "I made sure you couldn't ever use the stone again. That's why I left it out here like this. I knew you'd be dumb enough to just barge in and take it."
But Mikey was a child. Jon wasn't. A child touches a hot stove and gets burned, he learns not to touch it again. But Jon...
Jon grabbed the stone. This time he could hear a slight sizzle, a sound and smell unpleasantly close to bacon on the skillet. The pain was worse than any he'd ever felt. It took every ounce of his will to say his next sentence without screaming.
"I wish Mikey could never use the stone again!"
There was a flash, an urge to look away. Jon dropped the stone, though the sensations from his hand were only a little less painful for its absence.
Silence. Jon cradled his hand. Mikey stared. Jon's hand was horribly burned. Red and black and oozing everywhere. It felt like it was still on fire. Then there came a choked sob that Jon was surprised to find didn't come from his own throat.
"Th-that's not fair!" Mikey had tears in his eyes. "You cheated! You can't do that! It's not fair!" Mikey began to cry.
Jon took some satisfaction in that. Idly, he wondered through the pain, whether he should feel bad about this sudden fraternal schadenfreude.