The 51-year-old Love Don't Cost a Thing singer was spotted packing on the PDA with the 48-year-old Argo actor during a family dinner over the weekend.
J Lo and Affleck made heads turn when they showed up to celebrity hotspot Nobu in Malibu, California, and didn't try to hide their attraction for one another over the dinner table.
The duo looked crazy in love as they shared a steamy makeout session while dining J Lo's teenaged twins -- son, Max, and daughter, Emme -- and the Shotgun Wedding actress' sister Lynda Lopez.
In the photos obtained by Page Six, the rekindled couple are caught mid-lip-lock with the singer throwing her arm around Affleck's shoulder and touching his face with her other hand.
Some teens might be grossed out over the idea of seeing their mom plant an R-rated kiss on her new boyfriend, but Max and Emme allegedly didn't mind.
"Ben and her kids seemed comfortable together," a source told PEOPLE. "The kids kept chatting with Ben. Ben seemed great. He was smiling and laughing. They ordered a lot of food to share. Ben had a Diet Coke."
"They enjoyed a Sunday family dinner together," the Nobu insider revealed.
"Jen and Ben sat next to each other and were very affectionate," they added. "They held hands under the table."
While Affleck has now met J Lo's 13-year-old kids -- who she shares with ex-husband Marc Anthony -- the couple has yet to introduce Max and Emme to the Academy Award winner's three children.
The Justice League actor has three children with his ex-wife Jen Garner.
As Radar reported, the singer's twins haven't met Violet, 15, Seraphina, 12, or Samuel, 9, but they plan on connecting the children soon.
“Jen and Ben rushed into getting back together. They didn’t mess about jumping back into the relationship; however, they are taking things much slower when it comes to introducing their children,” sources tell Radar.
“Jen’s kids got very close with Alex Rodriguez’s family which is why they are not rushing. Both sets of children know who their parent is dating and at some point, both families will meet, just not yet," they added.
J Lo and Affleck have been inseparable since rekindling their romance last month following her breakup with A-Rod.
There are even rumors that J Lo plans on "moving in" with Affleck. She added fuel to the fire when she was spotted checking out schools near his fancy Los Angeles neighborhood.