Proto-Afro-Asiatic language
Proto-Afro-Asiatic or Proto-Afroasiatic is a reconstructed language spoken that gave birth to the Semitic, Chadic, Egyptian, Cushitic, and Berber languages. In Dominion the angels developed a language that they used on Earth amongst themselves so as not to be understood by humans. I theorized that it would've been created around the time of Proto-Indo-European, and likely in an area where many descendants of Proto-Afro-Asiatic were spoken. Consequently, the angels' language, Lishepus, derives all its vocabulary from either PAA or PIE—or a blend of the two. It's kind of a mess, but it worked well enough.
For those curious, my primary source for Proto-Afro-Asiatic roots was Christopher Ehret's Reconstructing Proto-Afroasiatic (Proto-Afrasian) from 1995. I haven't got the slightest idea how reliable this book is. I liked the theory, though—the way the Semitic languages got those root systems. I was influenced heavily by it in the construction of this language, as well as Sondiv, and I've used the principles from that book in other languages as well, though perhaps not to such a large extant.