A 19-year-old Seattle man was sentenced this morning to 21 months in prison for his role in a West Seattle prostitution ring involving teenage girls.

Mycah Johnson said that he and other members of the West Side Street Mobb, a street gang, sold drugs, committed bank fraud, sold guns and forced young girls into prostitution to bolster their image, according to plea paperwork. Johnson pleaded guilty in King County Superior Court on Friday.

King County prosecutors had sought the 21-month sentence for first-degree promoting prostitution with enhanced penalties because it is a gang-related crime, said Dan Donohoe, spokesman for King County Prosecutor Dan Satterberg. The maximum he could have faced was two years and three months in prison.

As part of the plea agreement, Johnson agreed to testifiy when fellow gang members DeShawn "CashMoney" Clark, Shawn Clark, Thomas "Mario" Foster, Gerald "Kradel" Jackson and Desmond Manago are tried together on Aug. 25, authorities said.

Prosecutors say the charges stem from a November sting operation in which members of the Seattle Police Department vice unit arrested a 19-year-old woman who had advertised sex services on Craigslist. The woman said DeShawn Clark forced her to commit sex acts for money, beat her and took her earnings, charging papers said.

Prosecutors said the woman led police to other women who had been forced into prostitution.

DeShawn Clark, who authorities say was the the ringleader, is charged with human trafficking, promoting commercial sexual abuse of a minor, promoting prostitution, assault, unlawful imprisonment and drug possession.

Foster is charged with promoting prostitution and assault.

Shawn Clark, Jackson and Manago are charged with promoting prostitution.

Johnson, in plea paperwork, admitted that he forced his teenage girlfriend to work as a prostitute. He told the girl how much to charge, who she could talk to and ordered her to give him all of the money she earned, plea papers said. Johnson said he advertised her services online, rented her motel rooms, bought her condoms and even took her to California last fall so she could work there for him.

Johnson said that during this time he didn't have a job but the prostitution paid for his clothes, video games, car and drugs, plea paperwork said.

"As a gang member, pimping out a girl gave me status with my fellow gang members," Johnson wrote in the plea papers. "Making money is important for respect within West Side Street Mobb."