Risking her life to save her homeland, Shabon, a princess from the Nine-Headed Dragon Archipelago, joins Souma's side in hopes of stopping an impending war. But with a fleet already en route to the hostile archipelago under his orders, Souma sets out to infiltrate the islands before they arrive. As he gathers information within the enemy territory, he finds that the real threat isn't their naval fleet, but a massive creature in their waters that defies all common sense...?! What strategy will Souma come up with to handle these two encroaching threats?! Find out in the thirteenth volume of the revolutionary administrative fantasy series!