Simplify the following text for a Grade 4 native English-speaking person.
Original: Upon their arrival in Spargus , Damas , the king , demands that Jak serve him in return for allowing Jak to remain in the city and to repay the debt for saving his life .
Simplified: Damas : Jak 's father . He was the king of Spargus City , and before that , the leader of Haven City .