Zilbagias the Demon Prince: How the Seventh Prince Brought Down the Kingdom Volume 4

With his training in the Rage family territory complete, Zilbagias returns to the castle to begin his preparations for his deployment to the front lines come spring. And now that he has secured permission to fly with Layla—despite the reluctance of those around him—the possibilities seem endless. But life quickly becomes a dangerous balancing act, as he must fight to secure a strong position within the demonic kingdom while trying to undermine it. He makes great strides weaving alliances with powerful actors throughout the castle that he inevitably aims to betray, but they seem to be keeping their cards close to their chests.

[From J-Novel Club]