Honkaku Yonin Uchi Pro Mahjong - Mahjong-Ou Portable ROM Download for Playstation Portable (PSP). Honkaku Yonin Uchi Pro Mahjong - Mahjong-Ou Portable game is available to play online and download only on Roms Games. Honkaku Yonin Uchi Pro Mahjong - Mahjong-Ou Portable ROM for Playstation Portable download requires an emulator to play the game offline. This Game is English (USA) Version and is the highest quality available.