Fria is the plot-twist hidden villainess from Werewolves of the Rockies, a story from Forbidden Worlds #17 (May 1953). She is the girlfriend of ski jumping champion Lars Norden, and they were heading to an important contest when their train suddenly stopped in the Rocky Mountain area due to a snowslide.
The couple left with a number of passengers to a nearby village, and it was after reaching the village that Lars noticed strange behavior from a group of men, who beamed over the full moon about to rise. A crevasse separated the couple, with Lars instructing Fria to go to the train until a bridge can be built. Later that evening, Lars learns the area's dark truth: it is actually a colony of werewolves. After spotting them changing, he realizes that one of them was with Fria, who was shown admiring the moon while her traveling companion turned heel and transformed into a werewolf, much to Fria's shock. Lars eliminated several pack members by cutting down the newly built bridge and sending them to their deaths, and went on the search for Fria.
Unbeknownst to Lars, Fria turned heel and became a werewolf herself, and she and another werewolf were approaching innocent bystanders until Lars arrived. After subduing Fria (while unaware it was his girlfriend he was fighting), Lars kills the second werewolf and later finds the hidden villainess in a nearby snowbank, believing to have fainted. Fria reunited with Lars and skied together on the latter's skis, with Lars expressing regret over the werewolf that escaped. At the end of the story, the evil Fria began her transformation and teased that his confrontation could happen again, cementing Fria's heel turn. The comic ends without revealing the fate of Lars or Fria.