Minoru Shiba is the youngest son of the Shiba family, and third child to the late Miya Yotsuba. Having a frail immune system, Minoru was carefully hidden behind the wall of his siblings, even living in the same house as them. Entirely loyal to only his older brother, Minoru's specialty magic remains discovered, yet hardly used. But when his siblings' friends come over to visit, his small world is thrown to shredder.