Tower Dungeon

The setting is a certain kingdom. In order to save the kidnapped princess of the kingdom, the Kingsguard squadron challenges the "Dragon Tower," a gigantic structure floating in the middle of the sky, but they are blocked by powerful demons.
A provocation is made by a neighboring village to replenish the injured personnel, and when a young man is sent to the tower, the wheel of fate begins to turn. A tale of sword & sorcery and labyrinth exploration begins.