Beddo no Shita no Himitsu

The Defense Army Headquarters is swept up by the tidal wave of passion ignited by its commander Colonel Rosenberg and his lover Hans.
The man x man couples are taking over the border including a captain of the imperial guard across the desert, a serious, young officer-in-training, and a spy from a faraway country, etc. There doesn't seem to be an end in sight to the platter of bishies! 
(Source: Houbunsha, translated)