John Mayer Helps Katy Perry Celebrate Her 28th Birthday at L.A. Costume Party
- Photo: Jackson Lee/NPG1 of 11
- Photo: PacificCoastNews.com2 of 11
- Photo: PacificCoastNews.com3 of 11
- Photo: PacificCoastNews.com4 of 11
- Photo: Teach/Fame Flynet5 of 11
- Photo: Rex USA6 of 11
- Photo: Rex USA7 of 11
- Photo: PHIL MCCARTEN/Invision/AP8 of 11
- Photo: Dan Steinberg/Invision/AP9 of 11
- Photo: Kevin Mazur/WireImage10 of 11
Katy Perry's 28th birthday isn't until October 25, but the superstar kicked off her festivities early with a wild costume bash on Friday.
Dressing as a sexy vampire, Perry was joined at Los Angeles venue Magic Castle by her on-again beau John Mayer, Kristen Stewart, songwriter Diane Warren, Neil Patrick Harris and America's Next Top Model's Johnny Wujek, among other celebs.
Though his lady was the evening's woman of honor, Mayer, 35, attended the bash with quite a head-turning get-up. To complete his vampire hunter ensemble, the musician donned a prosthetic nose and chin, according to JustJared.com.
During the bash, Perry -- who asked for donations to support the David Lynch Foundation for Transcendental Meditation in lieu of gifts -- only had eyes for on-again beau Mayer. "They were in their own world. She didn't even talk to her friends much," a partygoer tells Us Weekly. "It was just her and John. She's obsessed with him. She said hello to people but then went right back to him."
The on-again couple also feted Mayer's 35th birthday on Tuesday, with a low-key meal in New York City at downtown eatery Freeman's.
Rekindling their romance, Perry "believes she can change" Mayer, a source tells Us. "She doesn't want to be just another one of his conquests."
ALSO ON WONDERWALL:
Real 'RHOC' Dish
"Real Housewives of OC" star Shannon Beador dishes about her family, her relationship with Vicki Gunvalson and what to expect from the reunion!Watch Video »
Fall's Best Looks
New fashion trends are here! Take a look at celebrities rocking fall's best looks so far.Watch Video »
Diva Double Date
Beyonce and Alicia Keys double date with their famous hubbies on today's Celebs Gone Social.Watch Video »
Shailene Woodley and the stars of "Divergent" chat phobias and on-set injuries at the film's world premiere.Watch Video »
Kaley Cuoco spends time with friends and family -- and lots of horses! -- in the wake of her breakup on this week's Celebs Gone Social.Watch Video »
Tats for Love
From Heidi Klum and Seal to Ryan Sweeting and Kaley Cuoco, see which stars got tattoos for love.Watch Video »