A woodcutter, a high school student at a technical school, loves tinkering with machines so much that he can tell the condition of a machine just from the sound of metal. One day, as the hands of the pocket watch he was repairing struck the dead of night, what appeared before him was—a beautiful mechanical princess in a wedding dress, her arms bound by a demon mask!! She has come from the land of machines to the human world to escape from those who want to marry her forcibly, after they covet the power hidden within her body. A high-speed action and interspecies romance story drawn by a super-talented newcomer!!