Laethwyn was the love interest for Ray Palmer in the Sword of the Atom Mini-Series and Specials in the mid 1980s. Unfortunately, she went bye-bye when the Atom got relaunched in more traditional super-hero stories later. I think the horrible third Sword of the Atom Special also did something to kill the Sword of the Atom franchise, which was a wonderful homage to Edgar Rice Burroughs’ John Carter.
UPDATE: Updated to the color version. You can also buy a print of this drawing if you’re so inclined, over at DeviantArt.