Adarshan No HanayomeThe Bride of Adarshan, Adaru Shan no Hanayome

From Aerandria Scans: The small country of Castoria was conquered by the Adarshan Empire. To tie the alliance between the two countries, the victorious shogun, Alexid Deke Adars, was forced into a political marriage with Castoria's sixth imperial princess, Justinia. But she's only 10 years old...!