His hand closed around Hematite's wrist more firmly. It all looked a little ridiculous (and was probably a good workout for muscle groups of Hematite that he previously hadn't really known existed). His brow furrowed: and then, suddenly, black ripples arced down from his hand to Hematite's wrist to Hematite's palm to Hematite's fingers and it was electric.
The star seed had previously sparkled in his grip like static, but now he was pumping something else into it. The energy coursed from Charonite into Hematite's hand, oily and overwhelming, and his fingers involuntarily squeezed over the starseed -- pumped everything he could into it. Tisiphone's fair skin suddenly turned glassy and transparent, shining; a pale, shining apple green colour, shining out from within her, as though it was her entire make-up showing itself to the two of them. And there was black seepage from Hematite's hand moving up -- moving through her, with black steamy wisps coming from where his hand was dug into her ribcage.
The black was spread out all over her, devouring the green. And he could feel the starseed falter, then change.
When the black had swallowed her whole -- ending in a point at her forehead where the black star mark was -- the world was suddenly a blizzard of black feathers, settling everywhere, peeling off what had previously been Sailor Tisiphone. There was now a girl in a short black frock, pale hair spread out underneath her like a blanket, and she reeked so much of Negaverse energy it was almost overpowering.

Charonite slid Hematite's hand out of her chest. It closed up, leaving a ripped-out mark in her bodice.
"Finally," he said. "You did something ******** right."