It stands for someone who, despite having a captivating demeanor, is actually quite evil in terms of behavior, character, and Deen.
Acquiring any Portion of a Swine:
Acquiring the meat, blood, hair etc. of a swine means a person will or has acquired unlawful wealth.
Drinking the Milk of a Sow:
Drinking such milk means a person will commit evil through his intellect and wealth.