Dabi x Rias AU ROYAL dragons and princesses (Patreon)

Dabi is the prince, primogenitor of King Endeavor, ruler of the Northern Kingdom and Rias is a human princess, daughter of the only deceased King of the Southern Kingdom. Her grandmother decides to marry her to Endeavor's son so that the two kingdoms can merge. She does not agree with this proposal, but when she discovers that her future husband is a dragon thousands of years old, this could possibly be complicated, because as a human her time is much shorter. Will this be an impediment for both of them, or will love triumph with two totally different species?