That perked him up! Sleepy Kanye West takes a nap during fiancee Kim Kardashian's birthday bash... but wakes up when he spies her ample cleavage

It was his bride-to-be Kim Kardashian's 33rd birthday extravaganza on Friday night, taking place in one of the most exciting cities in the world - Las Vegas.
But it seems that all of the festivities over the last few days had finally caught up with Kanye West on Friday night.
The rapper, who proposed to the reality star earlier in the week on Monday night, appeared all tuckered out, and was snapped taking a little nap while standing up, as the couple and her famous clan hit TAO nightclub at the Venetian Hotel to celebrate Kim's milestone.

Wowsers! Kanye West was caught staring at his new fiancee Kim Kardashian's cleavage as they attended her 33rd birthday bash at Tao in The Venetian Hotel in Las Vegas on Friday night

With his arms crossed, Kanye had his head down and eyes shut while he appeared to be taking a little snooze.
The 36-year-old was no doubt exhausted, after planning his lavish proposal to the Keeping Up Kardashians star and also performing in his Yeezus world tour.
Earlier in the night on Friday, Kanye had taken to the stage at the MGM Grand Hotel & Casino before heading over the The Venetian to be by Kim's side.
But one thing certainly did perk the Touch The Sky singer up, and that was the sight of his new fiancee's figure clad a very low-cut white lace crop top and matching curve-enhancing pencil skirt.
At one point, Kanye was seen staring intensely at the mother-of-one's eye-popping cleavage with his mouth agape as they walked around the casino floor. 

Forty winks: During the night, Kanye, who had just performed at the MGM Grand Hotel & Casino, was also seen taking a nap while standing up

Sleepy: The rapper has had a big few days after proposing to the reality star and performing in his world tour

Uninterested? Kanye crossed his arms over his waist as he was surrounded by fans wanting to take a snap of the star at the party

Give us a cuddle: Kanye looked as if he was so sleepy, he need to rest his head on Kim's chest in a darkened corner of the nightclub

Never one to do anything in halves, Kim went all-out for her 33rd birthday party and made the most of her eye-popping post-pregnancy figure.
The reality star was in Las Vegas four days after her actual birthday.
'Let the bday festivities begin Vega$' the Keeping Up With The Kardashians star tweeted to kick off the party, along with a photo of herself in her cleavage-enhancing white lace ensemble.

Belle of the ball: Kim looked stunning in her choice of outfit as she celebrated her 33rd birthday at TAO Nightclub

Just like old times: Kim poses with her sisters Khloe and Kourtney as they arrive on the red carpet at TAO

You can tell she was the birthday girl! Not wanting to be upstaged, Kim dazzled in a white lace bustier and pencil skirt, to accentuate her famous curvacious figure

Happy couple: Kim and Kanye arrived together, with Kanye dressed in an eye-catching red blazer for the occasion

The look of love: Kanye looks down at Kim with adoration at her birthday party

Me and my man: Kanye and Kim got engaged earlier this week on the reality TV star's actual birthday

The clans all here! Kris Jenner was also there to celebrate her daughter's birthday

The corset-style top pushed the new mother's already large breasts up even more, as she stared demurely into the camera.
Joining the birthday girl were sisters Khloe and Kourtney Kardashian, and entourage Naya Rivera, Robin Antin, and new best friend, Blac Chyna.
While Kim's actual birthday will be hard to beat, with Kanye getting down on bended knee and proposing, nevertheless the reality star was dragging out the celebrations with her official party at Tao in Sin City.

That's how to celebrate a birthday! Kim poses alongside her four-tier birthday cake and the TAO girls

Make a wish: Kim poses seductively as she blows out the candles on her birthday cake

'Let the birthday festivities begin, Vega$': Earlier in the night, Kim posted a picture of herself with her pals

It timed perfectly with Kanye's concert at the MGM Grand Garden Arena, and the aspiring fashion designer met one of her professional idols backstage at the show.
'Yeezus time with Franca Sozzani,' Kim tweeted, as she posed with the editor-in-chief of Vogue Italia.
It wasn't just the youngsters who were excited to hit the famous Vegas Strip. Kim's mother, Kris Jenner tweeted a photo that night showing the stage that was set for her future son-in-law's show.

Mum and me: Kris put her hand on Kim's shoulder and looked full of pride at the spectacular shindig

Leather lady: The momager opted for an all-black leather look for her daughter's birthday party, complete with a knee-high dress, biker jacket and ankle boots

Just me! Kris pulls an excited face behind her daughter who appears calm and serene at her big birthday bash

All in black: Khloe and Kourtney both opted for black along with their mother

'YEEZUS....Tonight. Vegas. BRACE YOURSELF. #unstoppable #KanyeWest,' the momager messaged to all her followers.
As for the controversial name of his current tour that features Kendrick Lamar, West denies that didn't do it to intentionally cause a stir.
'I don’t do anything for the sake of controversy. I don’t do anything for the sake of publicity,' he told San Francisco radio station 99.7 NOW earlier this week.

Oh so stylish: Scott Disick puts his arm around Kourtney as the pair celebrate Kim birthday

That's dedication: Fans and tourists waited with their cameras at the ready, near the red carpet, to see their favourite celebs enter the party

The krew: Kim Kardashian shared this photo on Instagram after landing in Las Vegas with Kanye West and friends, including Tyga (second from left) and Jonathan Cheban (far right) on Friday

Kim and her new fiancé arrived in Las Vegas at lunchtime on Friday and naturally the first thing that the birthday girl wanted to do was pose for a photograph.
While they were at the airport, Kim and Kanye and their group of pals, including rapper Tyga and Kim’s best friend Jonathan Cheban, posed for a cool picture in front of some planes.
The gang leaned up against the bonnet of the car, but Kanye took it a step further and hopped up so that he was standing on the vehicle’s hood, as Tyga crouched beside him. Kim wasn’t about to attempt that in her high heeled sandals, so instead posed up in front of the car.

On top of the world: Kim posed in a rock chick inspired outfit as Kanye stood on the bonnet of a flashy car

Taking care of business: Kim Kardashian was seen tying back her hair as Kanye took care of business as they arrived in Las Vegas

Nice to meet you: Kanye West and Kim Kardashian greeted people as they touched down in Las Vegas

That's my man! Kim stood in the stands next to her mum as they watched Kanye West's concert at the MGM Grand hotel in Las Vegas before her birthday party

The blonde beauty went for a rock chick style look in a black T-shirt, skinny jeans, a gold chain choker and futuristic square black sunglasses.
Kanye, meanwhile, was wearing a red plaid shirt unbuttoned over a grey T-shirt, along with dark jeans and tan boots.