Severus was startled by the sound of Lily's voice, he had not heard her approach and even if he had, he had not expected her to talk to him ever again. He knew he had been mean calling her a mudblood, he was a half-blood himself after all. In his defense though, those bloody Gryffindor's had been getting on his nerves and Lily was a Gryffindor, guilty by association.
He looked up at the girl that used to be his friend, trying to keep any and all emotions of his face. "Lily." He greeted not able to keep the suspicion out of his voice. Looking passed her for a moment to check if more of her house were there before looking back at her through a curtain of his black hair.