Unless the object of the singer’s affection is a vampire, surely what Hart means is unphotogenic. Only vampires are unphotographable, but affectionate ‘-enic’ rhymes are hard to come by.
Stephen Sondheim, Finishing the Hat: Collected Lyrics, 1954-1981, With Attendant Comments, Principles, Heresies, Grudges, Whines, and Anecdotes
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