Kim Kwang-jin, 30, stepped into the limelight when the activist from the remote southern city of Suncheon became the 19th National Assembly’s youngest member in April. The baby-faced rookie legislator was also a boon to the main opposition Democratic United Party badly in need of an image makeover.

Within less than a week, the party’s best asset turned into its biggest nuisance for retweeting curses against President Lee Myung-bak and hints at kinky sexual preferences.

The controversy forced party floor leader Park Jie-won to apologize Tuesday and emboldened the Saenuri Party to attack the ethical standards of the left.

“Though Rep. Kim’s inappropriate SNS postings were made before he acquired his lawmaker status, I am sincerely sorry,” said Rep. Park.

“I have repeatedly urged Kim’s self-restraint, but he did not accept the warnings.”

His apology is designed to contain the public backlash against the lewd remarks Kim made well before he joined the parliament.

“I love slave games, getting naked, handcuffs and whips and all,” Kim wrote on his Twitter back in 2010, apparently addressing a male counterpart.

“You bring all the stuff but don’t worry about clothing because you won’t need it for the next five days,” he continued.

These provocative postings came to attention as Kim recently triggered controversy through a series of comments, including referring to renowned war veteran Paik Sun-yup as a “traitor to the people.”

The focus of the debate, however, soon shifted to Kim’s sexual remarks and abusive language.

“I sometimes hug my female juniors or strip off my male friends. I guess I could be cornered as a sex criminal, then,” he also wrote on his Twitter in June.

Ironically, the lawmaker has been actively involved in sex crime prevention activities, submitting a number of related bills.

Kim also used abusive terms against a conservative civic group, as well as retweeting someone who said his new year wish was President Lee Myung-bak’s sudden death.

Such self-indulgent behavior of the novice lawmaker rose as a major obstacle for the DUP and its presidential candidate Rep. Moon Jae-in, ahead of the Dec. 19 presidential race.

The liberal party had suffered a heavy blow before the April general elections due to raunchy jokes and sexually violent remarks made by former lawmaker Kim Yong-min.

By Bae Hyun-jung (tellme@heraldcorp.com)