Robin Williams's 'Mork & Mindy' Co-Star on His Alleged Sexual Antics on Set: 'I Never Took Offense'

Robin Williams’Mork & Mindy costar Pam Dawber is opening up about her complicated on-set relationship with the late comedian.

In a new book about the actor’s life titled Robin, the former actress, 66, said Williams was “such a nice person” who had a “gigantic heart,” according to excerpts obtained by The Daily Mail.

“I really loved Robin and Robin really loved me. We just clicked,” she reportedly said in the upcoming biography.

However, Dawber also opened up about Williams’ alleged sexual behavior on the show, which helped skyrocket the actor to fame. “I had the grossest things done to me by him. And I never took offense,” she reportedly said. “I mean I was flashed, humped, bumped, grabbed. I think he probably did it to a lot of people … but it was so much fun.”

Dawber added, “Somehow he had that magic. If you put it on paper you would be appalled. But somehow he had this guileless little thing that he would do – those sparkly eyes. He’d look at you, really playful, like a puppy, all of a sudden. And then he’d grab your [breasts] and then run away. And somehow he could get away with it. It was the '70s, after all.”

Mork & Mindy producer Howard Storm, who was also interviewed for the book, reportedly said, “He’d be doing a paragraph and in the middle of it he would just turn and grab her ass. Or grab a breast. And we’d start again.”

Storm allegedly added, “It was just Robin being Robin, and he thought it would be funny. He could get away with murder.”

Garry Marshall, another producer, reportedly said that it was Williams’ mission to embarrass Dawber on set: “He would take all his clothes off, he would be standing there totally naked and she was trying to act. His aim in life was to make Pam Dawber blush.”

Williams took his own life at the age of 63 in 2014 after suffering from Lewy Body Disease, a type of dementia that affected his thinking, memory and movement control.

His wife, Susan Schneider Williams, opened up in a PEOPLE and ABC interview in March about the “quiet, intellectual” man she knew and loved — a far cry from the explosive personality often seen on screen.

“Robin was a quiet, intellectual man, sometimes playful. But primarily what moved him was the fact that he was an observational genius,” she said. “And if you can imagine the energy that he would bring to the stage — no one can do that full-time. And I think the brilliance behind that impact of energy he would bring was because in his time off, he was someone who was contemplative and an observational genius.”