Probably her own erotic imagination. Erotica, unlike pornography, requires imagination. Erotica might shock, but it's unlikely to offend. Naked bodies of men and women have been enjoyed aesthetically from time immemorial. There really is no need for surliness and raincoats.
Erotica is out in the open.
And what's more, it's no longer a male domain. Female erotica is big business. Libertine , a first erotic novel for Queenslander Peta Spear, may be to your liking. It is the story of a young woman who becomes the wartime mistress of a general. Like all good stories it does have themes, these being summarily 'choice' and 'freedom'.