Many people say things like this as a joke, but for Nick, becoming his father is serious business. As we learn from Ambrose/future Nick, if Nick turns evil, he will become a Malachai like his father, and the safety of the world will be in danger. That's some serious business.

This is the goddess Artemis speaking to Ambrose—i.e., future Nick. Is love just a pet name, or is it possible for a goddess to love someone who is essentially her manservant?

Nick shouldn't be worried about becoming his father, because here is a major reason why the two of them are different. Nick is motivated to preserve the wellbeing of others. Adarian only cares about himself. Night and day, folks.