SEOUL (Reuters) - When South Korean President Park Geun-hye turned to a lawyer known as her “Bulletproof Vest” to defend her in a corruption case that could lead to impeachment and criminal prosecution, she may have had little choice.

Yoo Yeong-ha, speaks during a news conference at a prosecutor's office in Seoul, South Korea, November 15, 2016. Park Se-yeon/News1 via REUTERS

Although Yoo Yeong-ha is not among the country’s better-known lawyers, he wears his die-hard loyalty to the embattled president as a badge of honor, a rarity for Park as the scandal around her deepens.

A remote figure even at the height of her popularity, Park has now been deserted by many of her allies, including her own justice minister.

For weeks, hundreds of thousands of people have come out on the streets of Seoul demanding Park resign. Her current popularity rating is just 4 percent, a record low. On Thursday, she made her first public appearance in over three weeks.

Yoo is slightly built and youthful-looking for his 54 years. Dressed casually in jeans and a sweater under a knit jacket, he met Reuters at a location he insisted be kept confidential to fend off media attention.

“I did not hesitate even one second when offered the job as her lawyer,” he said, speaking over sips of flower tea. “I have complete faith in the president.”

Yoo was a legal adviser to Park’s Saenuri Party, standing for parliament three times under its banner, and losing each time.

Park, then a lawmaker, gave Yoo a ringing personal endorsement during his unsuccessful 2008 run for parliament.

“Candidate Yoo Yeong-ha is a partner with whom I have long thought and felt alike, and a person that I know and trust more than anyone else,” Park said in a videotaped statement.

Yoo said he meets with Park in the presidential Blue House, where he takes notes by hand as he is not allowed to take his personal laptop inside. He later transcribes his notes to a desktop computer.

Yoo declined to provide details of his conversations with Park, 64, but described her as calm and strong.

“Korean presidents in general are lonely. She is keeping a cool head now and I believe she will get through this dark tunnel,” he said.

DEFERENCE AND PROFANITY

Yoo refers to Park deferentially and calls her his political mentor.

However, he became known for profanity-laced tweets in defense of Park during and after her successful presidential campaign in 2012.

“Can you just shut your mouth and be quiet? To your eyes 51.6 percent of people look like Nazi traitors?”, he tweeted in 2012 to a famous novelist who was critical of Park, after Park won with 51.6 percent of the vote.

That kind of language led local media to nickname him Park’s “Bulletproof Vest”.

Yoo later closed his Twitter account, and acknowledged that emotion may have gotten the better of him.

As a criminal lawyer, he is best known for defending a teenager in a notorious rape case eight years ago. The defendant was initially convicted but his jail term was suspended on appeal.

Legal experts said Yoo’s loyalty secured him the president’s brief.

“This case is very difficult for lawyers to take because public anger is so strong,” said Lee Heon-hwan, a professor at Ajou University Law School in Suwon, south of Seoul, adding it made sense for Park to hire a lawyer she trusts.

“Her scandal is so messy and fuelling so much anger. Her lawyer will also get blamed, rather than being able to raise his or her name value.”

Rho Young-hee, a lawyer at Seoul law firm Cheon Il, said Park’s hiring of Yoo shows how much she prizes loyalty.

“I wouldn’t take that case even if I was offered. I don’t want my life to be ruined,” Rho said.

CARELESSNESS

Park is alleged by prosecutors to have colluded with a long-time friend, Choi Soon-sil, to enable her to wield improper influence in government affairs and in fundraising by two foundations set up to back Park’s initiatives.

Park has denied wrongdoing but acknowledged carelessness in her ties with Choi. She has offered to resign, but the opposition has said it will vote next week on whether to impeach her.

On Wednesday, Park appointed a special prosecutor who will take over the probe by state prosecutors.

She is protected from indictment as long as she is president but she remains subject to an investigation and would lose her immunity if she leaves office.

Yoo declined to discuss his legal strategy. He said he is working day and night to defend Park during the investigation, and has lost 4 kgs (9 lb) since he was appointed on Nov 15.

“I never surrender to what is wrong, I don’t back down,” he said. “It is my calling to clear all allegations laid against the president and find the truth. I am going together with the president till the end.”