He whipped round and stared at her. "What?" he said again, before finally taking in what she'd said and lowering the sword. "Oh, sorry, sorry!" He looked around vaguely for something to clean it on but could see nothing, so he got out his hanky and wiped the blade as well as he could with the rather meagre bit of cloth.
He wasn't wearing a scabbard, because he'd just grabbed the sword up when he heard the noises in the other room, so he just leaned it against the nearby building and tried to rid his mind of the image of his Slayer dead on the floor. He stared at Romana again, speechless and bewildered.