One of the characters out of the series, Slumuttown, he's Honidarai's right hand man. He's usually the first and only one that could get his hands on Honidarai's most prized slaves, and he usually likes when they struggle against him, for it turns him on more. Ephemeral makes his first appearance in Chapter 3, but his name isn't mentioned until Chapter 5.

And that, my friends, that thing he's holding...has metal claws on the end.

If you're into wanting to read the slightly maturated story, then here's the first chapter: http://www.furaffinity.net/view/2177999

Oh, and definition of Ephemeral:
e⋅phem⋅er⋅al
   /ɪˈfɛmərəl/ [i-fem-er-uhl]

–adjective
1. lasting a very short time; short-lived; transitory: the ephemeral joys of childhood.
2. lasting but one day: an ephemeral flower.
–noun
3. anything short-lived, as certain insects.