A victim of retired Big Apple financier Howard Rubin — who allegedly “tortured” former Playboy models and other women in a Midtown penthouse-turned-BDSM “sex dungeon” — celebrated his arrest and called the wait for justice a “complete nightmare.”

Rubin, who worked for years at George Soros’ investment firm, allegedly lured “dozens” of women to New York City between 2009 and 2019 — where he tied them up, beat and electrocuted them, the Brooklyn US Attorney’s Office.

“Relief. Relief. After eight years, finally a breath of relief,” the accuser, who requested anonymity and was believed to be the first victim to speak publicly about Rubin’s arrest, told The Post.

“It’s just been a complete nightmare. I’m relieved that justice is finally being acknowledged.”

When told Rubin, 70, was held without bail, she replied: “Oh my god, thank God.”

Rubin — known as “Howie” or “H” and worth at least tens of millions of dollars — has been accused of binding and gagging his drugged-up victims so they weren’t able to object to sexual torture.

Text messages with his assistant, Jennifer Powers, who is also facing sex-trafficking charges, detail some of the stomach-churning escapades, including one instance where they laughed about electrocuting a tied-up woman’s genitals.

“I don’t care if she screams,” he allegedly wrote, along with the laughing face emoji, in another sickening message, the feds said.

The allegations against Rubin first came to light in 2017, when he was taken to civil court by three Florida women who accused him of violent sexual assaults. 

Lawyers who brought forward those lawsuits — and represented nine of the 10 victims referenced in the indictment — noted the victims’ long ordeal.

“My colleagues and I investigated Mr. Rubin and Ms. Powers and prosecuted sex trafficking claims against them for seven years,” lawyer John Balestriere, who repped victims from Florida and NYC, told The Post.

“As such, we are very glad the US Attorney’s Office relied on us during the last few years to provide them information which was essential to their case,” said Balestriere, who no longer represents any of the victims.

Two of those victims were described in court papers as Playboy Playmates, including Amy Moore, and a third, Stephanie Caldwell, was identified as a model and a dancer. Another model and student from Atlanta, Emma Hopper, is also part of the civil litigation against Rubing and Powers.

It’s unclear what prompted the feds to move forward with the criminal case now, and his victims have been left questioning what took so long — especially as prosecutors brought other high-profile sex trafficking cases to court.

“It’s been incredible because we sit here and we watch Epstein and we watch Diddy and we are saying how did this happen so fast when it happened after us? Other people are getting their answers, but not us,” one of his alleged victims said.

The woman said she heard from the FBI that the arrest was delayed until the civil litigation played out, and sources say the feds plan to try to use Rubin’s testimony in that case against him.

A jury found Rubin liable, but cleared Powers at a 2022 civil trial. Rubin appealed and the case is pending at a mid level federal appeals court.

Prosecutors have since claimed that Rubin — who pleaded not guilty and was held without bail — admitted to flying women across state lines and paying them upwards of $5,000 for sex.

Authorities believe “dozens” of other women were recruited for sexual encounters with Rubin, and said at least 10 others were believed to have helped facilitate the sick schemes.