Some guys wait their entire lives to meet the girl of their dreams, but Rihito is already living with three of them! How did a high school freshman get so lucky? Well, the truth is that Anne, Aines, and Lene aren't normal girls: they're Shinki - 6-inch-high, customizable androids that are the latest hit in the toy world. Don't let their tiny size or doll-like appearance fool you; these little ladies have more than full-size intelligence and emotions, and, since each one would secretly prefer to be Rihito's favorite, there's always a little mechanical friction going on. Then, what happens when a fourth Shinki, Hina, is suddenly added to the mix? Get ready for sparks to fly as four battery-powered princesses take charge of Rihito's world in BUSOU SHINKI!