My Sister and Girlfriend Are Enemy Domestic Traitors!

The boy's father was once the military god of the Ford Federation. Unfortunately, he was assassinated after losing the First World War. After that, his life completely changed. Struggling to survive amid surveillance and assassinations, he finally discovered that his sister and girlfriend were all spies sent by the enemy country! The power named Graveris is the last hope he has. In resolving crises one after another, the various plans left by his father gradually surfaced.