>>2837673There's a contrast between its socially agreed-upon position as a filthy excretory organ with no sexual purpose or appeal and the reality of it being another cute pink hole that twitches and tightens in response to sexual stimulation which I think greatly elevates the eroticism of the anus.
If I were to try and explain things concisely, it would go like this: every woman has two budding flowers on their body, one of which they are conditioned to be deeply ashamed of. They hide the bud of this shameful flower away from the light so that it may not bloom or be seen by anyone. As a result, there's an erotic significance to the act of defying this shame and allowing the bud to be observed and appreciated: it's an acknowledgement, acceptance, and indulgence of the observer's desire in spite of personal reservations, that will ultimately prove enriching to the self as well. Thus the clouds part, the flower blooms, and its beauty is mutually recognized.