Okay I didn’t read more than you did but yes because he was failing at getting pregnant of anyone because his womb has too much mana so it needs someone stronger or with bigger history than the duke and there’s no one in the kingdom other than the king and that’s why he changed his appearance to have sex with the king (and he didn’t want to openly have the king’s children because otherwise he would be not his heir but the king’s but with the fact that he’ll have twins maybe one will be the duke’s heir and the other one the king’s heir or maybe both would be both)
I think so
MEGA SPOILER
PLZ SPOIL ME
DUKE RAY GAVE BIRTH TO TWIN BOYS COPY OF HIMSELF
BUT QUESTION WHO IS THE OTHER FATHER????
IS IT HIS MAJESTY????