For every light there must be a shadow, and the stronger the Light, the stronger the Shadow it produces.

The power of the Amp Gem has the ability to give or take energy as it's master's heart sees fit. Morally good people give and receive energy from the Gem making a self sustaining loop of energy that radiates energy to nearby friends if the keeper desires, where as a morally corrupt person only receives energy from the Gem, and if they desire, other people.

Once someone's heart stops sending energy to the Gem the gem reacts by receiving negative energy from it's surroundings and forces them into it's keeper, thus, revealing what is in their heart. Even someone as pure and innocent as Rose can not hide what her heart desires for long.

I so wanna use her in a Yadere meme. Does such a thing exist? XD