Hyakujitsu no Bara / Maiden Rose [OVA]

The story takes place in a fictional world that has just begun a great world war. Klaus von Wolfstadt, from one of the nations of the “Western Alliance,” has left his duty as a soldier to his nation in order to be a knight to Taki Reizen, commander of the 15th division “Rozen Maiden” whose country has an alliance with “Eurote,” an enemy of the Western Alliance. The story follows their romance as it evolves from friendship, to love, and finally, to hatred.