So from what I understand is that they are first rank because of the tower. They have reached the 80 something level in the tower when everyone is stuck in the 40-50 level. How he did that is still kinda vague but what I do know is that he genetically modified the race of all the people in the kingdom to be the dark celestials that are a lot stronger than an normal celestial. Also a lot of his skills are tied to how much trust and love he has for his vassals so that’s why he worked so hard to gain their trust and love. I don’t think the mc is much of a fighter but he is definitely a support fighter. He can cast a lot of buffs on the others based on how much love he has for them. And this definitely does not mean like sexual love I guess. He sees the vassals as family. Now the grand duke is a different story.
So his kingdom is so strong because of the power of love. lol.
Im waiting for the time for the uke to actually fight. It will be interesting to see him that way because they're the first rank empire. I want to know the specific details too on how he made his empire to be the first rank one. This is such an interesting manwha and I'm planningmarinate this maybe for a year or two.