There's no way to know exactly who the two kings are without more context. They could be fictional characters created for the story, or they could be based on historical kings from different regions.
The 3 Wise Kings were probably astrologers or scholars from the East. Their names are often given as Melchior, Caspar, and Balthazar, though there are different versions in different traditions.
Well, they're important because they were among the first to recognize Jesus' significance. In the 3 Wise Kings story, they came from afar. They were guided by a star, which was like a divine sign. Their presence added to the grandeur of Jesus' birth. They were like messengers from different parts of the world coming to pay homage to the new - born king. Their gifts also had a role in providing for Jesus and his family in a practical sense, as gold was a precious resource.
In the Twilight universe where this fanfiction is based, the Volturi kings are Aro, Caius, and Marcus. They are the leaders of the Volturi, an ancient and powerful coven of vampires.
The two kings and two little kings were called the Double King Bomb. In the game of Fight the Landlord, the Double King Bomb was the biggest card type, which was a bomb composed of two kings and two small kings.
While waiting for the TV series, you can also click on the link below to read the classic original work of "Dafeng Nightwatchman"!