Rama Singh is a brute of a man who killed the 20th Phantom by stabbing him in the back after betraying the Singh pirates by telling the 20th Phantom secrets about the Singh pirate fleet.
The 20th Phantom and Rama had a relationship before the betrayal.
After Rama killed the 20th Phantom he was given leadership and the Island of Gullique as a base. He and the men used the island for smuggling plus also an illegal casino.
One of Rama's men killed Rama as he was blowing up the island after being outed by the 21st Phantom as a traitor to the Singh Brotherhood.