William Tenn's "Party of the Two Parts" (novelette, humor, free): Cross-species "pornography" peddling
This has the feel of a Jack Vance story - not style-, but content-wise. Very colorful descriptions.
Knowing Tenn, I won't be surprised if the legal farce that this story is satirizes some aspect of US administration or society of 1950s - something with a universal appeal, however. But I cannot pinpoint.
Story summary.L'payr is a habitual criminal on his home world Gtet, & about to be sentenced to life in prison for peddling pornography to minors. He escapes to the primitive earth, a sort of reservation of galactic government with a lot of restrictions on activities of advanced aliens.
On earth, L'payr will manage to sell his pornography to Osborne Blatch, a human school teacher, in exchange for fuel. Only, the two have different perspective on things exchanged. Human cannot see anything erotic in pictures, but thinks they're invaluable as illustrations of alien biology. And valuable-for-alien fuel is cheap stuff in any chemistry lab in a school.
Complications arise - for the galactic cops - when human publishes a biology textbook with these illustrations, effectively peddling alien pornography to human minors...
Fact sheet.First published: Galaxy, August 1954.
Download full text from Internet Archive.
Included in Ellen Datlow's SciFiction classics.
Related: Stories of William Tenn; First contact fiction (annotated, but much smaller list).