It happened in the Black Dragon's forest. The Black Dragon was deemed far too frightening to be allowed to enter the human's land, thus he was ordered to remain at his forest for the signing and the agreement of the peace treaty while the Saintess would come to visit. They thought it would be a difficult deal considering the Black Dragon with his mightiest power will disagree to the said arrangement.
Much to their surprise, he agreed.
He didn't come alone. Instead, he had brought with him his guardians who declared they wouldn't allow the King to meet those tricky humans alone. There were vampires, werewolves, mermen who were now on their human feet, and the dragon folks who was swayed by the idea that they don't have to live in a hiding anymore.