A matched pair of burlesque dancers charge in a shocking new lawsuit that they were pressured to perform “twincest.”

In papers filed in Manhattan Supreme Court, “Porcelain Twinz” Heather and Amber Langley say the owner of a Manhattan nightclub bullied them into performing sexual acts on each other in private with him and on stage in their erotic show.

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While the Langleys had made a ca reer out of simulating sex acts with each other on stage, they “are identi cal twin sisters who never before have engaged in incestuous sexual relations with each other either privately or professionally within the confines of their perform ance art,” their suit says.

“That’s not what we’re about,” Heather told The Post.

The suit seeks unspecified money damages. Accused ha rasser Simon Hammerstein, co-owner of The Box, where the twins performed, had no comment.

The sisters said they were invited to perform a two-week stint at the up scale, Lower East Side bur lesque showplace – whose patrons have reportedly included Moby, Jay- Z, Jude Law, Cameron Diaz and Lindsay Lohan.

“It was the opportunity of a lifetime for our careers and something we were very excited about,” Heather said. Hammerstein offered to put them up in his loft above the club when they arrived on July 9, 2007, they say.

Their trial performances led to a long-term contract, and the twins retrieved their belongings from Portland, Ore. When they returned, they were stuck stay ing with Hammerstein, and he “commenced a campaign of sexual harassment,” the suit says.

“He felt free to treat them as his porcelain toys to play with at will,” said their lawyer, Jack Tuckner.

The twins finally found their own accommodations in November, but needed Hammerstein to sign as a guarantor, the suit says.

That’s when he called them in to his bedroom “to talk” – and they found him lying on the bed in his underwear, the suit says.

He told them to get in to bed with him, and “required” them “to remove their underwear before demanding” oral sex from them, the suit says.

He then allegedly ordered them to engage in oral sex with each other.

Around the same time, he also allegedly demanded they change their erotic show to include “actual sex acts” with each other using sex toys.

The sisters “believed if they did not alter their performance,” they “would be fired,” the suit says. They followed orders, and the club changed the name of their act to “Twincest.” Amber called it a “huge compromise,” but “we made it very artistic so we could hold our heads high.”

The act went on until last July, when they said they finally quit after the owners pushed them to take their show further.