Demon King Is a Loyal Wife of The Human Knight Commander (Completed)

Reincarnated from a Common Human from Earth to the child of the Demon King, Zenzur, bear the fate of his brethren in his shoulder the moment of his awakening. Always serious and strict his face never has a time of sheer jovial moment except when he rescued a young human child and give her the status of his future fiancee. Everything is getting smoother when he become the supreme ruler of Demon tribe with his terrifying power. Everyone thought he will ransack and kill humanity now at his peak but he actually cut his two humongous horn and offer a peace treaty to humans. The demon tribe are all dissatisfied and felt betrayed but they couldn't do anything to the Lord Demon King. Alas, the Demon King pushes through negotiation and finally going to bring peace to his brethren and human but then betrayed by the human girl he cherish as his sister coupled with the demon who is dissatisfied with the Lord Demon King. One of them is his trusted and sole friend who promise to release him from eternal seal once they killed all the human. 500 years past. The seal broke as it cannot contain the power of the Lord Demon King forever. Demon King who in his last moment believes that atleast one, atleast one will get him back is full of sadness. Walking in the unknown path of grass, Demon King finds a handsome knight with a fiery red hair getting out of the white horses. Badum...Badum.. The suppress heart of a man who likes other male beats uncontrollably. Yes. The Demon King suppress himself for liking other male because of his status and responsibility but.....well....they did discard him so....Isnt it time to find his heart desire? He then kneel down and propose to the red hair knight who is taking a leak in the tree. <<My original work>>