Sabrina, the Teenage Witch (1996)

S1E17 First Kiss

As Sabrina and Harvey's relationship deepens, her aunts share a surprising fact: when a witch kisses a human for the first time, the human transforms into a frog. Despite the warning, Sabrina can't resist kissing Harvey, leading to an unexpected consequence. Now, she must figure out how to reverse the spell and turn him back into his original self.