Angel

Angels, according to the mythology of many species, were spiritual beings that served God as his messengers.

Popular Earth depictions of angels often presented them as beautiful humans with halos and/or wings, not unlike Solonians in their "evolved form" (TV: The Mutants), Light (TV: Ghost Light) and the Weeping Angels. (TV: Blink) Members of the Heavenly Host, robots designed by Max Capricorn, resembled angels by deliberate design. (TV: Voyage of the Damned) James Court, who worked in Earth theatre in the late 20th century, had often observed a special effect wherein a "hastily-assmbled combination of feathers, muslin and stage lighting" created the appearance of an angel from the audience's point of view. (PROSE: Vampire Science)

Encounters
On several occasions, people encountered what appeared to be actual, existing angels.

Peri Brown once met an angel named Yy, who was "more than just woman or man", androgynous and "unbearably beautiful". They had fallen from Heaven, and after selling their wings for a cheeseburger, Yy was imprisoned on Sheol. Peri convinced Yy to return, and helped them close the Gates of Heaven. (PROSE: The Ruins of Heaven)

Iris Wildthyme, for her part, was well-acquainted enough with an archangel called Gabriel to play gin rummy with him for the Ark of the Covenant, (PROSE: The Unhappy Medium) though it is worth noting that in his eighth incarnation, Iris's friend the Doctor once claimed that he and "the archangel Gabriel" were one of the same. (PROSE: Vampire Science)