Justin Bieber is taking a little time away to celebrate Sofia Richie's birthday!

The 22-year-old pop star was spotted cuddling and passionately kissing his bikini-clad girlfriend in Cabo San Lucas, Mexico, on Saturday, according to Daily Mail. Bieber apparently also bared his behind during the trip.

WATCH: 13 Times Justin Bieber and Sofia Richie Proved They Were Fashion Soulmates

Bieber and Richie jetted out of town on Friday in celebration of her birthday earlier this week, and Richie has been happily chronicled their vacation on social media.

Judging by the sweet Snapchat photos, it looks like Bieber pulled out all the stops for his model beau. Their weekend has included candles spelled out to say "love," flowers, and sunset views. Aw!

Richie captioned a pic of their bed on Saturday morning -- which featured an amazing beachside view of the ocean -- "Not getting up."

WATCH: Sofia Richie Celebrates Her 18th Birthday With Justin Bieber, Rocks Two Crop Top Looks

She even sweetly captioned a photo of their beach chair set-ups as simply "happy."

As if those snaps weren't jealous-inducing enough, Richie also shared a breathtaking pic of her beach view via Instagram.

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Bieber is all about his new girl, even if that means he may never come back to Instagram. He deleted his account earlier in the month, after fans left some not-so-nice comments about Richie on his posts.

A little social media drama isn't enough to keep Bieber from Richie, however. Though he skipped her birthday dinner on Tuesday, he made it to her party later in the night.

Find out more Richie's birthday bash in the video below.