MANILA, Philippines -- A singer filed a complaint at the National Bureau of Investigation (NBI) against an alleged fake doctor who botched a butt augmentation procedure on her more than a decade ago.

Selina Sevilla, whose real name is Sharon Simon, filed the complaint at the NBI Special Action Unit against the fake doctor, who was known to her only as Dr. R. A. Eugenio.

Accompanied by her lawyer, Sevilla claimed Eugenio injected silicone oil on her buttocks 11 years ago. She added that she experienced adverse effects that would require her to undergo surgery to be treated.

She narrated that Eugenio did the procedure at his house, which also served as his clinic, on Dominga Street, Malate, Manila. She said she paid Eugenio P20,000.

"I went to his clinic twice. The second time was a few months after the first procedure when I noticed that the size of my buttocks were uneven, so he fixed it," she said.

However, after a few years or about five years ago, she felt pain and she noticed that her butt started discharging an oil-like substance.

"When I was in London, since it was cold there, my butt started to feel very stiff. Then eventually, my butt started to be deformed, so I consulted another doctor who told me that there was an infection," she said, adding that she was seeing the same doctor who treated Josie Norcio, another victim of a botched butt augmentation procedure allegedly by a former doctor of the Belo Medical Clinic.

Eugenio was reportedly popular among entertainers, including sexy stars, bar girls, and those working as entertainers in Japan. He had many clients then, Sevilla said, adding that she came to know Eugenio through her friends who underwent the same procedure.

"During my time, it's embarrassing to admit that you underwent cosmetic surgery, unlike now when stars even became endorsers of cosmetic surgery clinics," she said.

She added that she underwent the procedure because of her work. "Competition was very tough. It?s not enough that you have a beautiful voice, you have to be beautiful, a complete package."

Sevilla's lawyer, Rey Edgar Dazo, said his client was studying the possibility of filing charges of illegal practice and reckless imprudence resulting in serious physical injuries against Eugenio.

NBI Special Action Unit chief Angelito Magno said authorities had Sevilla?s statement and were set to coordinate with foreign embassies after learning that Eugenio was abroad.

"We are now tracing his whereabouts," Magno said. "We conducted background check on him and we are 80 percent sure that he is not a real doctor."