Brody Jenner and his girlfriend Avril Lavigne celebrated his 28th birthday at The Bank Nightclub at Bellagio Resort & Casino. We're told Brody had just flown in from Montecito where he attended step-sister Kim Kardashian's wedding to Kris Humphries.

Bruce Jenner's sexy son didn't pose with his ladylove, but her name could be visibly seen on his forearm. That's true love!

Once arriving in Sin City, Brody Tweeted: "The ship has arrived! VEGAS TIME BABY…Gonna be a great one."

Brody and Avril dined at Yellowtail Japanese Restaurant & Lounge ... munching on signature dishes like Big Eye Tuna Pizza, Rock Shrimp and Lobster Carpaccio by Executive Chef, Akira Back. The sexy duo, and a group of friends, then headed to The Bank ... leaving around 4:00AM.

Sounds like a sinfully delicious night all around!

He's gotta look good for his ladylove, Avril Lavigne!

Brody Jenner took his sexy self to a Vitamin store in Malibu, where he loaded up on healthy goods and a veggie-infused drink.

But we can't stop staring at Jenner's left arm -- it says "Avril" so big, no one can mistake whom he belongs to.

When you've got a man this smokin' hot, we can understand why you've got to tag him.

Good thinking Avril!

Avril Lavigne and Brody Jenner have been dating since last February, and they're still going strong -- could this be the real deal?

Jenner and his punk rock princess hit up Kitson on Robertson Blvd., and it looks like these high rollers practically bought out the store!

Lavigne recently put the Bel Air home she shared with ex-hubby Deryck Whibley on the market. The ex-pair bought the eight-bedroom, 10-bathroom mansion back in 2006, and the singer is now offering it up for a cool $9.5 million.

Does this mean Avril and Brody will be moving in together soon?

Find out where the sexy pair got matching ink, after the jump ...

Yesterday Avril Lavigne and steady beau Brody Jenner went shopping at Whole Foods in Malibu, and the duo couldn't keep their hands off of each other! Av stuck her paw in Brody's pocket in the parking lot, and we spotted the lovebirds smooching inside the store while they waited to check out.

You'd think these two were still in the honeymoon phase of their relationship, but they've already been together for over a year! X17 snapped the first photos of Avril and Brody making out in April of 2010 at the Chateau Marmont, and clearly the Hills hunk and the Canadian punk/pop star are still super sweet on one another...

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Avril Lavigne loves her boyfriend Brody Jenner, and apparently his half-sister Kim Kardashian, too!

Kim and beau Kris Humphries joined Avril and Brody at New York hotspot SL to celebrate the release of the pop sensation's newest album Goodbye Lullaby.

The "So Complicated" singer even serenaded her sexy man, and by the look in his eyes, he's loving it. Such a cute black tutu, Avril.

A green and white cake was presented to the punk princess in honor of her big day, and we're told Ciroc specialty cocktails were flowing.

What a sexy foursome!

See Avril and Kim working the green carpet ... after the jump.

Avril "I'm Not Madonna" Lavigne was nice enough to take reality star boyfriend Brody Jenner with her to Paris - here's the happy twosome leaving their hotel together - where she's promoting her upcoming album Goodbye Lullaby, set for release in one month.

The singer's latest single, "What The Hell," recently debuted to low numbers: 13 on the US chart and 29 in the UK. But Avril isn't bothered.

"It's been a few years," she admits to Vanity Fair. "The response has been really great, so I'm happy."

Any chance her album will be as popular as Gaga's and Britney's?

Yes, even pink-haired punk rocker Avril Lavigne likes to stop by Fred Segal in West Hollywood once in a while. Especially when she's with current boyfriend Brody Jenner. The still going strong couple looked as happy as can be, so congrats to them!

Think Brody's really gonna pop the question on New Year's Eve? And if so, will Avril say yes and walk down the aisle (again)?

On Wednesday afternoon Avril Lavigne and boyfriend Brody Jenner hit up Bristol Farms in Beverly Hills for a few last minute Thanksgiving items, and these lovebirds look like they're still in their honeymoon phase! AvBro wore matching black hoodies, and what was more newsworthy than getting a peek at the former Hills star's recently buzzed hair? Observe:

Since when did the Canadian punk/pop tart smile for the cameras? It must be true love, because she was never this happy with ex-husband Deryck Whibley!