In a land where demons roam the Earth, Guardians have always protected the villages. The role has always been passed from father to son—until one Guardian's wife gives birth to a daughter. So the doctor and his assistant decide to quietly switch her with another baby, the newborn son of a local shop keeper.
The world of Ed Cho and Lee Cherolis' Little Guardians has long existed according to a simple, if reactive, system. Each village has a Guardian, who protects the village from the occasional demonic incursions. Eventually, the Guardian will have a son, whom he will train to become the next Guardian of the village, and so on.
But on the night that the Guardian Tane's wife dies in childbirth, she gives birth to a daughter, not a son. Tane is away battling a demon at the time, and in the next room, the wife of Yunda, the shopkeeper, gives birth to their second son. So Doctor Marburger and Nurse Hazeldella make a choice they feel is best for the village: they switch the infants, giving Yunda a daughter and Tane a son.
So Subira grows up sweeping the floors and stocking the shelves of Yunda's item shop (the sort you'd visit in a fantasy video game for a quick hit of healing potions), resigned to her quiet life. Idem, meanwhile, is stumbling through his Guardian training. He loves and admires Tane, but can never quite live up to Tane's expectations. Hazeldella wrestles with the secret of the children's legacy, wondering if she and the doctor made the right decision.
But unbeknownst to either Subira or Idem, trouble is brewing in their world that could force both of them to embrace their destinies. A woman named Soma—who, despite being a woman, seems to have the powers of a Guardian—arrives in the village with tales of a demon army forming. She recognizes the same Guardian abilities in Subira, and wants to train her, just as the other Guardians train their sons.
Little Guardians deals a lot with the tension between tradition and intuition, though it manages not to thoroughly condemn the former in favor of the latter. Tane is a child of tradition, and tradition has served him well. And, although he wants to stuff and mold Idem into a perfect image of himself, he truly loves the boy he has raised as his son. Idem might respond better to Soma's brand of training, which emphasizes a deep connection with one's spirit animal and negotiating with demons instead of leaping straight to violence, but it's hard to argue with Tane's results. It's likely Tane and Soma will need to rub off on each other in order to defeat the dangers ahead.
And this isn't just the tale of a girl who has been deprived of her birthright by a sexist society in favor of an inept boy. After all, this is Little Guardians, plural. Idem may not have been born with the innate abilities of a Guardian, but he has the desire to learn and has spent his life learning from Tane. This isn't just Subira's story, but the story of two children defying the expectations of the long-held tradition that Guardianship passes from father to son. And with a demon army on the rise, the world will need as many Guardians as it can get.