I Agreed to Keep a Low Profile for Three Years, but What the Hell Is Going on with the Skeletons Giving Birth to Babies?

I, Kuina, the most useless blood descendant of the Demon King is rumored to be. But in fact, I have already signed a contract with the gods. As long as I can be the lord for three years, I can have invincible power. In order to live peacefully until three years later, I kept a low profile and chose the most barren demon territory, quietly waiting for the three years to come. —— I, Robin, a clever time traveler, a subordinate of the Waste Lord. Because of my useless lord's position as the unintentional demon king, in order to prevent me from being liquidated due to the failure of the lord to inherit the throne, I have to stand up. Fortunately, I got a golden finger, which allows me to cultivate an unlimited legion and become infinitely stronger. So I used my golden finger to work hard, plunder resources from all sides, cultivate legions, and fight in all directions, ready to put trash on the throne! —— As a result, many accidents occurred in this remote and barren fiefdom. "You mean, I gave you a few skeleton soldiers and you trained me an army of the undead?" "What, I woke up and you found a dark ore in my territory, and everyone is tempted to attack me?" "I asked you to send the dark ore out to appease them, and you defeated them all?" Kuina was stunned. She obviously only wanted to live in peace for three years, so why did things become like this? Robin began to offer suggestions again: "Now we still have the ninth-level Bone Legion, the ninth-level Demon Molten Legion, and the ninth-level Dragon Legion. How about we just fight the Demon King?"