Are Requiem arrows real?

Could you please clarify for me if Requiem arrows are indeed a tangible, physical entity or merely a concept within a fictional narrative? I'm curious to know if there's any evidence or documentation suggesting their existence outside of, say, a popular video game or literary work. It would be fascinating to learn if these arrows possess any unique properties or characteristics that set them apart from traditional archery projectiles, should they indeed be real. Could you elaborate on this matter?