Alisa stood on stage with one corner of her mouth lifted. This is one illustration of a contempt expression. It is an expression that means hatred/disdain and it represents the feeling of look down on others.
Contempt is a basic emotion that every human experiences (regular basis). It is a dangerous emotion because of its lasting effects. It can also be a lack of respect/reverence for something. "One corner of her mouth lifted" is a classic example of a contempt expression.