Trope-a-Day: Naughty Tentacles

Naughty Tentacles (since removed from TV Tropes, but I think we all know what this one is about, yes?): Given that there are species with tentacles, and Boldly Coming is in effect, this does happen (consensually). However, no-one out there would understand why humans in general and the Japanese in particular are so obsessed with it, nor would those involved appreciate the interest in their sex lives.