At Aoi Academy, a prestigious school for gifted magicians, Kazuki Shikimori, who is only 17, struggles with his comparatively low magical aptitude. Students are only given a specific number of spells, and exceeding this limit results in disintegration. However, his troubles multiply when Yuuna Miyama, Kuriko Kazetsubaki, and Rin Kamishiro, three girls fixated on Kazuki's genetics, suddenly appear. Kazuki aids them despite his inadequate magical reserves which gradually decrease as a consequence. This added pressure may prove to be his downfall.