Perry, 27, looked pretty for the night out in a short, see-through red floral dress. The "Part of Me" singer changed into black flats after the party and carried her tall red platforms. Mayer, 34, wearing a cowboy hat, white dress shirt and jeans, escorted Perry to their car.
After Russell Brand filed for divorce on Dec. 30 after 14 months of marriage, Us Weekly was first to spot Perry on a hot date with Mayer at Soho House in West Hollywood on June 19. "They were affectionate, holding hands and cuddling!" an observer told Us. Mayer, a notorious ladies man, has been previously linked to Jennifer Aniston, Jessica Simpson and Jennifer Love Hewitt.
"They're just hooking up right now," a source recently explained. "It's not serious -- yet!"
But Perry -- who's also casually seeing musician Robert Ackroyd -- has had a thing for Mayer for years. At NYC's Goldbar on Sept. 11, 2009, an onlooker recalls, "She made it her mission to hook up with him."
And now, the insider said, "She nailed down her crush!"