Gerichtia, the dragon witch, with a punitive nature. Endless lists of laws float in her barrier. She will tie a noose around the neck of anyone who dares break it. The more devious of her familiars are suspended from the ceilings, considered signs of her wrath as well as warnings.
It was over. The Scourge Sisters were no longer.
After Vriska Serket had fought and defeated what could only be Terezi Pyrope's witch - she saw the transformation with her own eyes, she saw her die right in front of her - she picked up the grief seed, crushed the heinous object in her fist, and sought Cuebey for the rest of the night with fierce determination that no other could have rivalled; not even Terezi herself, who had been suspicious about Cuebey ever since the beginning. She, being a bit of a judicial system buff, was meticulous and precise in her ways and found it odd that a walking, talking thing that belonged on the edge of a cuestick could just materialize right in front of her and say that she could have anything she desired, as long as she promised to fight witches as a magical girl (he didn't mention that eventually she'd either die in battle or become what she was fighting against - there was no physical contract and thus it wasn't even in the fine print.)
"You fucking rat!" she hissed when she finally found the cueball-headed creature sitting in the back of an alley, instantly recognizing him for his lack of facial features, little green suit, and the occasional crackle of raw spatial energy that accompanied him. "You tricked us, you worthless sack of shit! You lied!"
"Contrary to your beliefs, I didn't trick you," Cuebey said, "as lies of omission do not exist. I never lied to you; I simply left out some of the more intricate details. It would be more of a joke if the matter at hand wasn't so serious - of course, I don't mean your fate, which is indeed inevitable."
The azureblood clenched her fists around the brittle grief seed which had remained in the palm of her hand, tears streaming down her face. "We hated each other's guts, I'll give you that, but - but I didn't want her to die! Especially not because of you, for fuck's sake! If I'm not allowed to get angry over our 'inevitable fate'," and here she mocked the tone of her deceiver, "then what's the matter at hand?"
"You know, I'm merely a pawn," said Cuebey. "As soon as I reach my energy quota, this universe will be of no more use to me and the few of my kind working on different planets. I do have unlimited bodies, until my master deems the amount of energy we've collected satisfactory. We will die, and he will enter. His plans simultaneously prevent the heat death of this universe and allow him to tear it apart himself while your civilization watches."
"What...?" uttered the Puella Magi, "what the hell?"
If Vriska were to say more, Cuebey did not allow her to continue. "I am simply the orchestrator of your demise, to put it grimly. But really, you'd be dying for this universe, in a way." The incubator turned sharply on its paws and left.
Vriska Serket began to sob.