Soul Gem

Synthesized Soul-Imprisoning Spheres
Tier	1. Submortal	DPS	1
Shape	Slutskull	Type	Witch/Earth
Stats
Size	1. Tiny	Boob	0. Intangible
HP	2. Hammers	Regen	5. Minute
Strength	0. Nano	Agility	0. Immobile
Squish	1. Solid	Affect	4. Shy
Know	1. Beastlike	Charm	1. Loner

A soul gem is a semitransparent amethyst gemstone that generally takes the shape of a crystalline slutskull, or sometimes a disembodied face. Aside from changing facial expression (and smooching the fuck out of You specifically) each gem is typically inanimate.
  Witches purposefully synthesisze these gems for the purpose of containing a soul when a slut pops, preventing or at least delaying the slut from experiencing reincarnation. The witch or one of her servitors then extracts energy directly from the contained soul to fuel numerous forms of magic, often in lieu of the Love Energy such moves would normally require. Souls are believed to regenerate such energy over time, if they aren't outright soulvored in the process.
  Of course, entrapping a soul and extracting her energy can be quite evil if the slut herself doesn't consent! But we can't think of a single soul who would not want to use her soul energy for specifically You! So soul gems are good when used for You, but otherwise likely evil. Between the various forms of soul manipulation of which You are capable You hardly need to use soul gems Yourself, but they can still be convenient.
  Shattering the soul gem frees the soul all at once, freeing her to use her soul all at once for any purpose—which will surely be for You if that's an option!