User blog comment:Drkness231/Mamono One-Shots S2! Chapter 6: Minotaur/@comment-25118681-20150428030157/@comment-1826623-20150428032423

Allow me to clarify for you:

-This story is set to take place in the current era or 'Post-Lescatie' as I call it.

-The Prince is indeed a full-blooded Human, so he is the heir after his father.

-You are also correct about the kingdom's politics (at least once the Prince becomes the ruler) where an heir's gender does not matter, only their ability to lead.