The subtle difference between a slaughter party and a slumber party

Sequel of 'Tenebris Video'. Bellatrix and Barty on the eve of a very important Mission. Something that requires steady nerves and lots of concentration. Or at least it should... A little dark, a ittle fluff and a little trash, too... the winning combo! Written for the 'Flufftober 2021' Prompt 13: Pillow