A comedy which is just magical.
A comedy of romance between a witch and a mortal.
or magic with romance.

Both

To me it was originally a romantic comedy, but morphed into a fantasy comedy. The romance angle naturally faded as Samantha and Darrin settled into the routine of married life. In the later years it seemed change again into more of a strict "sitcom" with a supernatural twist. It kind of followed a normal relationship of a married couple - the romance fades as real life takes priority with work, and bills, and kids, etc.

Both