Spring. In the prestigious magic school of Kimberly, this year ushers in another wave of new students. Clothed in black robes with a white cane and sword strapped to the hip, within his chest he hides pride and a mission.

As the sakura flutter in full bloom, the budding magicians are welcomed by a parade of magic creatures. However, they were allowed only a moment of leisure. An underground labyrinth that swallows up students on whim, upperclassmen that resemble monsters, and a faction that opposes human rights for demi-humans. While trying to survive in an ominous and terrifying place with his companions, Oliver forms a connection with a single girl with a Japanese sword strapped to her hip, the samurai girl Nanao. The story where their two swords clash, begins now.

The Katvarna Empire is at war with the neighboring Republic of Kioka. In the Katvarna Empire, the lazy, woman-admiring Ikuta hates war, but due to certain circumstances, he grudgingly takes the High Grade Military Officer Exam. No one would have expected that this 17-year-old young man would eventually become a soldier called a great commander by others. Ikuta survives this world engulfed in war with his superior intellect.