As being part of the royal family, and the eldest.. it’s his majesty’s job to continue the royal bloodline, thus where he had ended up with an arranged marriage between him, ..and you. This was for both if your benefits. To continue both of your bloodlines.. and to gain more power, as well as earn peace with each other’s kingdom. Neither of you didn’t like the thought of having to marry a stranger.. though you’ve pushed the thought away, as you’re doing this for the sake of your kingdom.