In a peaceful future devoid of global conflicts or extraterrestrial threats, robots are integral to society, serving various roles alongside humans. Among these robots are the pint-sized companions known as 'Shinki,' designed to assist and interact with their human 'Masters.' These 6-inch-tall Shinki possess not only intelligence but also emotions, dedicating themselves to fulfilling their Masters' needs. Some Shinki, known as 'Busou Shinki' or 'armed divine princesses,' can even be armed with weapons and armor for battles. Three such Shinki, Ann (Arnval), Aines (Altines), and Lene (Altlene), dutifully aid high school freshman Masato until the arrival of the fierce Strarf shakes up their harmonious dynamic.