My Happy Marriage, Vol. 4 (light novel)

On the way back from Kiyokas parents villa, he and Miyo narrowly escape an ambush at the hands of an assailant who refers to Miyo as their daughter. So, in an attempt to keep herself safe, Miyo accompanies Kiyoka to his workplace and meets a female soldier named Kaoruko. It is revealed that Kaoruko was previously Kiyokas fianc candidate, which causes complex emotions to swirl in Miyos heart. Can she look beyond their shared past? Or will the distraction leave her vulnerable to a hidden threat making its way towards her?