The protagonist, Ryuu or Crying Dragon, is a mysterious man who often plays games with the gang members. He only wins by "ron", a move in which one needs to wait for the opponent's tile to complete the win.
'Ron' is also called 'Naki' in mahjong, which has the same pronunciation as 'Crying' in Japanese.
Mahjong Hishouden Naki no Ryuu is a mahjong anime based on a manga by Nojo Junichi in 1980s-90s.