Usato is dragged along by accident when two classmates are summoned to another world as its heroes, and while they are trained as front-line fighters, he turns out to have rare healing magic instead. That should make him support staff, but it lands him under Rose, the fearsome captain of the kingdom's Rescue Team, whose training for healers has nothing gentle about it. Between Rose's regimen and teammates like Amako, Usato becomes a very different kind of healer than anyone expected. This light novel is the source material for the anime adaptation.