Mr WPNZ

Mr. WPNZ takes on a guardian-like role toward Cory, Katie, and Zack, but his version of parenting is twisted. He disguises questionable practices as games, such as gun training, encouraging them to be assassins like their mother in order for them to be strong. He is shown to be ruthless and reckless to successfully achieve his goals, he turns innocent people like Mario into practice targets and injures Karen's allies to isolate her. Obsessed with Karen and her children, he stalks them relentlessly, forcing her to keep them hidden. His expertise in weaponry and mechanics makes him extremely dangerous, often requiring multiple people to take him down.

Mr. WPNZ in truth, is a bloodthirsty psychopath who only sees his children as mere soldiers. While he originally loved Karen, he was by no means a loyal partner to her, abandoning her after her children were born. Although he did seem to care about his kids at first so this might be more of him going back into his normal established cruel mindset of an assassin rather then trying to explicitly hurt his kids.