Theobroma, or Criollo, is a brown-coloured sweet. It opens the mind to magical influences by relaxing the mental defenses. Magicians in Sitia use to as a training tool where a fledgling magician is close the subject.
It was used on the Commander to break down his mental defenses. Using it in this manner is considered to be the same as rape.
The only way to break the control is to kill the person using it.