"Sirius hated the look on his cousin's face." Bellatrix, condemned to an abusive engagement, has changed far too much for her cousin's tastes after the news, and is in a downward spiral no one can seem to pull her out of. But Sirius finds there may just be a way, and he's more than willing to fulfill the role she needs him to play. Blackcest, Cousin Incest, Sirius/Bellatrix