Araquiel: A fallen angel who guarded the secrets of the signs of the earth. Araquiel is named in the Book of Enoch, where he is said to have fallen after giving into the temptation of beautiful mortal women. One of two hundred Watcher Angels charged with overseeing humanity, Araquiel abandoned his heavenly duties to raise a family instead. Although the knowledge was forbidden, he taught the signs of the earth to humans, further breaking his trust with Heaven.
Source : Dictionary of Demons by Michelle Belanger