Sabrina: The Animated Series S01 E04 Tail of Two Kitties

Sabrina enters Salem in a cat contest and Harvey enters his cat in a contest. When Harvey's cat wins Salem meets up with that cat and finds out that she's his lost lover. Suddenly they renew their love lives and start dating again but Sabrina overhears her and says that she plans to marry Salem so she can turn back into a witch again!