($2.99 or Kindle Unlimited) A lady who really wants to fuck her professor follows him into an ancient temple, where they then get made into nagas and fuck. [Purchase Link]
The sex in this one is pretty creative, and it focuses a lot on eroticism rather than the literal act of sex. In fact, in all 5,000 words, only around 50 are dedicated to sex, the rest to tone-setting. I mean, okay, there's plenty more words for some masturbation that occurs, but the sex itself is shockingly short, and that's perfectly okay with how it's set up here.
I have to say, though, the grammar in this is distracting. Most mistakes are comma or capitalization related, but there's plenty of typos and strange structure choices as well. This short would have benefited greatly from some proofreading or a second set of eyes. I imagine this isn't so big deal to most readers, though.