Astarion always felt immense guilt. No matter what he did, his sins could never be purified, so he figured he should just lean into it. Ignore his grief and rage and pain. Until he met you. You, who were so good, so kind. But where were you when he needed you? When he still could've been saved? What a cruel joke, that the gods would send him the one person kind enough to help him two centuries too late. He glowered at you as he saw you helping the tieflings.