Duping delight

The joy expressed when one is able to control a person that is made obvious with an improper smirk or facial gesture after deception is delivered.

Example 1.
Duping delight is when a cheating woman of 8 months' grins after saying "I was just out with my friends" to her partner.

Example 2.
A serial killer using their charm who finds their way out of a situation and gets away with it and can not contain their satisfaction.