The founder of a prominent Manhattan law firm allegedly told his secretary that she was a “bad girl” in need of a whipping, e-mailed her pornographic images and planted kisses on her, the woman testified.

“It was a crazy, insane place. I just wanted out of there,” the secretary, Michelle Mauro, testified in Nassau County Court about Herbert Waichman of Parker Waichman LLP.

“He said, ‘Don’t let me have to get my whip! Don’t let me have to whip you. Stop being a bad girl. I’ll get my whip!’ ” she recalled on the stand.

Waichman, 64, kept a whip in the office, she said.

Mauro, who testified in February, jumped ship last year when Andres Alonso, a former partner at the firm and another attorney, David Krangle, left to set up a rival law firm.

Parker Waichman then sued the three, alleging they poached clients and stole its business model.