Qinai de Dianxia

One is the unloved 1st prince, the other is the 2nd prince who is the heir to the throne with high hopes. They are the royal family of the Wim Kingdom and destined to be incompatible with each other. However, a letter changed their relationship. To hide the secret, he doesn't hesitate to make himself his partner, and he is willing to sacrifice everything to gain his love.

(Source: POCKET COMICS)