- The appendage is alien/nonhuman, people are fascinated by something out of the ordinary.
- The scenario can be anything from lewd woman getting off to fantasy rape.
- Penetration, deep penetration, all the way through, no penetration, any number of 'special' attributes, etc, all possible.
- Usually, no human dudes are involved. (As an example, I tend not to want human males in my porn at all so this fits.)
- They range from sentient beings to feral creatures to plants to pure energy to ovipositors and more.
The list goes on and on. Basically, tentacles are a fantastical creature of the imagination, and so can easily fit in anyone's imaginings. They provide a
huge utility in erotica simply out of sheer possibility, and people make use of it often and well.
