A little from world-concept things.

Shaia is a pretty impulsive and unpredictable nation, so keeping good realations with this country is important for Wassem. Buran, as a king of Wassem, gifting one of the best creatures for riding to the Shaia's ruler. Wassem is known for many rare and elite species only they can grow up and sell. You can see pretty informal atmosphere here, maybe it happened just after some ceremony or something - it's pretty rare case to see two liders together on someone's territory.