Beware, J-Law!

Jennifer Lawrence hit L.A. theme restaurant Medieval Times sans serious boyfriend Nicholas Hoult -- and with John Mayer!

"They were playful and nudging shoulders," a source tells Us Weekly of the Hunger Games actress, 21, and the notorious singer, who's had bad breakups with Jessica Simpson, Jennifer Aniston and Taylor Swift. During the kitschy outing with other pals, the "Shadow Days" crooner wore medieval garb and was "implying that he wanted to get [Jennifer] drunk," the source reveals.

Find out more about this surprising night out in this week's Hot Stuff video, as told by Us Weekly's Senior Editor Ian Drew with special guest, actor Mircea Monroe, from Showtime’s Episodes.

Also in the roundup: More on Anna Paquin's pregnancy, why Jason Segel relishes being a "father figure" to love Michelle Williams' daughter Matilda Ledger, and more!

Watch the video now!