Two things I have learned recently:

1. There are examples of tentacle erotica from 19th-century America (and earlier):

Click to embiggen

“Lewd and Abandoned”. Caricature of notorious New Orleans prostitute Emma Johnson, from “The Mascot”, 21 May 1892. Johnson is depicted in a window with a fan, with tentacles reaching out to the sidewalk entrapping passers by, including men, an old man, an adolsecent boy, and a young woman.

2. If you do a Google search for public domain pictures of octopi, you might stumble upon a Wikipedia talk page for tentacle erotica, which, fortunately for my taste, only has pictures from 19th-century America.

Photo credit: By Staff of “The Mascot”, New Orleans [Public domain], via Wikimedia Commons.