I love how fairy tales can sneak up on you with surprisingly sophisticated characters, and the classic 'beautiful monster' most readers point to is the Beast from 'La Belle et la Bête'. The earliest full-length version of that tale was written by Gabrielle-Suzanne Barbot de Villeneuve in 1740, and she’s usually credited with creating that particular blend of monstrous exterior and tragic nobility. Villeneuve’s Beast is far more layered and complex than the short moral fable people later read; his backstory is elaborate, and the tale examines class, transformation, and the idea that outward ugliness can hide an inner worth.
Jeanne-Marie Leprince de Beaumont later condensed and adapted Villeneuve’s version in 1756 into the shorter story that schools and children’s collections popularized, so a lot of readers associate the Beast with Beaumont’s cleaner moral framing. Across centuries the Beast has been reshaped—Jean Cocteau, Disney, and contemporary novelists all retell him differently—but Villeneuve’s creation is the seed. For me, the Beast remains endlessly compelling because he’s both monstrous and heartbreakingly human; that paradox is why I keep returning to retellings and reinterpretations, always spotting something new about how beauty and monstrosity can coexist.