A New Jersey labor lawyer’s alleged romantic involvement with the president of a union his firm represents is adding fuel to a lawsuit charging the president breached her fiduciary obligation to the union.

The lawyer, Richard Loccke, and the president, Hannah Twomey, have lived together for several years in a house Loccke owns, according to Kathleen Fonti, who is suing Twomey and the Health Professionals & Allied Employees union under ERISA.