Archangel Reyla is a low-key Archangel enjoying a quiet afterlife of slaying shadowlings, granting human wishes... and crocheting. Out of the blue, she gets a text from Archangel Gabriel, who she's never met before. Because of her high rating and aptitude for fighting (Reyla's great with a bow), she's being scouted as a possible member of The Echelon, an elite group of Archangels who are privy to the afterlife's secrets.

Archangel Gabriel will be in charge of training Reyla, as well as another Echelon candidate named Mikah. Gabriel makes her nervous, and Mikah is critical of her in a way that's highly frustrating. Not only that, she doesn't want the extra attention! Still, Reyla decides to undergo the special training to sate her curiosity. After all, what's the worst that could happen?

School for Spirits: Loneliest Archangel features a more adult set of characters, while retaining the spirit (pun intended) of the series.

Content warning: Mentions of suicide, sexual assault