The 31-year-old woman, who is scheduled to take her vows at a Turin convent this fall, said the picture was taken three years ago at a Sicilian beach, ANSA reported Wednesday.
The lawsuit seeks to have the picture, labeled by the poster as a "topless nun," removed from the social networking site.
ANSA said the picture has gathered a number of borderline lewd comments.
''If all nuns were like her, I'd become a priest," one comment reads.
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