Truth Serum
Harry Potter starred at his most hated professor in shocked. Did he actually say that out loud? Harry looks around and sure enough, everyone else was starring at him. Ron even had his mouth opened in surprised and eyes wide.
"Mr. Potter, I believe the truth serum is indeed working," Professor Snape said calmly and coldly.
"Um..." Harry was loss for words as he didn't know what to say to the man.
Severus sneered as he turns around. "Detention tonight, Mr.Potter," was all Snape said before heading back to the front.
"Ron?"
"Yeah mate?"
"What did I say?"
"You don't know?" Ron asked, surprised again. Harry shook his head. "I'll tell you later mate," he said after seeing the 'look' that he got from Professor Snape.
Harry nodded and everyone resumed on what they were doing before the incident as Severus cleared away the truth serum.