"NO!" Snape was frustrated by his multicolored shadow.
"But why not?!" Sarah sighed, whining undertones to her voice.
"Because," he hissed to her. "Go to the common room."
"Will you come?" she asked hopefully.
"NO!" he roared.
"…why?" she asked quietly.
He pounded his fist on the desk. "Do I need to give you a detention?"
"Can I really have one?" she smiled as if she'd won the Quidditch Cup.
"No."
Sarah pouted. "Please?"
"NO!!"