Maunburuten is a member of the Impostor Straw Hat Pirates. He tried to impersonate Sogeking.
The Fake Franky, who's real name is unknown, is a member of the pirate crew of Demalo Black. Due to the two year absence of the famous Straw Hat Pirates, they were presumed dead. Black had the idea for them to take on the identities of the Straw Hats for their own purposes. He took on the name of Straw Hat's sniper the Sogeking.
Maunburuten is an antagonist in the One Piece series that was created by Eiichiro Oda. The series first began serialization in Weekly Shōnen Jump on August 4, 1997. He first appeared briefly at the beginning of the Fish-Man Island Arc that began in Volume 61.
His first appearance was in One Piece Volume 61 CH. 598 "2 Years Later", and his first anime appearance was in One Piece - Episode 517 "The Beginning of The New Chapter! The Straw Hats Reunited!". His character in the Japanese series is voiced by Yao Kazuki, and the U.S. dub produced by FUNimation has yet to be announced.
The Impostor Straw Hats were celebrating their success at a bar in Sabaody Archipelago. Black's plan had worked and they were gathering pirates with bounties over 70 Million to join their crew. Their flyers ha drawn the attention of over 100 strong rookie pirates. There celebration was cut short when a long-haired woman at the bar refused to join Black. She said she was waiting for a man. Fake Sogeking laughed that he was probably some weakling who would beg for Fake Luffy's forgiveness when he showed up. The woman gave her last warning that she wasn't interested and claimed to not know who they were. Fake Nami went to threaten the woman's insolence, but they were all captured by a giant monster plant from a man with a long nose. Those two left together, and the room was filled with black clouds that blasted them with lightning. After stumbling out of the bar, Black ordered them to kill those two as an example.
While hunting the town for those two, Black shot two innocent people who just happened to look similar, and he was accidentally knocked to the grown by a young man passing by. When Black threatened the young man, both he, Fake Franky, and the rest passed out for some unknown reason. They woke up and Drip, who's the Fake Sanji, and Fake Zoro reported at Cocoa, Fake Robin, had been abducted by World Government agents.
They then gathered to Grove 46 for the recruitment meeting they arraigned. This meeting was brought to an abrupt end by the Marines with Sentomaru and the Pacifista Army of cyborgs. These PX-Series were able to out Demalo Black and the rest in front of the hundred pirates they had fooled. Black was taken in, but the rest of the Impostor Straw Hats were left to the dangerous pirates Caribou and Coribou. They begged for their lives, but Caribou used his devil fruit powers to drown Drip in mud. Fake Sogeking tried to stop him, but the blast of his gun passed through his body. They all are presumed dead.