I have so many favorite hc for blackinnon, but my all-time favorite is Sirius having a bad feeling the night Marlene dies and telling her not to go home, to spend the night in his house, to stay together-- but Marlene thinks he is being paranoid and goes to visit her home, and ends up dying there with her family. I just love the idea that Sirius lives with the regret that only if he insisted more, maybe that wouldn't have happened.