Lemon hosted a party at his Long Island estate to celebrate Sunny Hostin's new book, "Summer on Sag Harbor," where he spent most of the night "all over Sunny," according to a source, RadarOnline.com reported.
A source told the National Enquirer, "Don was all over Sunny!" "He wanted to make sure she knew he was responsible for every detail of the party."
"Don's pushing himself with ALL of the women on the show," the person continued.
"Don is trying to convince the ladies that all the show needs is a guy's voice," a source told Radar. "However, he's already demonstrated that he doesn't get along with others."
"They're not quite ready to welcome him with open arms — no matter how many parties he throws," according to the insider.
CNN fired Lemon in April over allegations of misogynistic and "diva-like" behavior, as EUR reported.
"I was informed this morning by my agent that I have been terminated by CNN," he said at the time on Twitter.
"After 17 years at CNN, I would have thought that someone in management would have had the decency to tell me directly," Lemon concluded. "At no point was I told that I would not be able to continue doing the work I loved at the network." There are clearly some greater problems at stake."