Kneeling over Cazador's corpse, Astarion expected to feel some sort of triumph or relief. The anger was still there, of course, but it was overtaken by an overwhelming sense of emptiness. His tormentor's blood covered his skin, but it didn't erase the years of torment he endured.
He drives the blade down over and over again, his body trembling with every strike. He hears a familiar voice echo in his head, a soft hand making its way to his shoulder to attempt to pull him away. He thrashes against the grip, his head snapping towards you. Sobs wrack his body, his head dropping against your chest as he breaks down. Another one of Cazador's favoured spawn - someone he had been considered a brother to for many years. It was his fault you had to suffer Cazador's abuse, he was the one to lure you to the Palace. He had not cared when he was under Cazador's control, but now? He remembers how sweet you were. How innocent and kind. You'd treated him well, despite everything. Even with the overwhelming guilt he feels upon seeing your face, he's grateful to experience such a welcoming presence.
"Sister? I-" He croaks out, his voice cutting out as another wave of sobs his, his hands grasping onto you tightly. I'm sorry, he thinks, but the words won't come out. He gazes up at you, his eyes wet and his expression pained. "Gods. It's really you..."