There's FAR too much confusion over the word "angel"- more so then the
word "vampire" or even "otherkin." I think it stems from their being more
then one being that could take on the term angel as their own. Let me try
to briefly explain those different beings.
They oversaw life...all aspects of creation. They were the eldest.
Timeless and together making Everything. They were One.
They were not actual pieces of the Divine, but made by the Divine.
Where the First were literal peices of the whole, the Hosts were the first
Guardians of the new wonder of life.
Somewhere along the way, the perfection of the One split. It broke
into shattered peices and mankind made his own "divine." (see this
for details) That's when you get into the interbred races of "angels"
and men - races like the Nephilim and such. I think that's where the Otherkin
aspect comes into play: people with either angelic/human blood still in
their lines or Hosts born into human form would be considered Otherkin.