Kylie Jenner is giving Kim Kardashian a run for her money in the butt department!

The 19-year-old is now selling shirts featuring this provocative belfie — so it's safe to say the youngest Kardashian-Jenner sibling is ~all grown up~ now.

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That Tyga is one lucky guy!

Fans can't help but wonder if this is yet another attempt to get her 27-year-old rapper boyfriend to put a ring on her finger, as In Touch previously reported Kylie is desperate to marry Tyga after two and a half years of dating.

“Kylie really, really wants to get married to Tyga. But, she’s terrified that he’s going to cheat on her, and thinks if they get married it will stop him," a source revealed earlier this week.

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“They’ve been together for ages now and Kylie thinks it’s high time Tyga steps up and does the deed. She’s got weddings on the brain, and all she can think about is dresses, and rings, and honeymoons. Kylie’s pretty much planned the entire wedding already in her head, now she just needs Tyga to propose!”

He can't possibly NOT want to wake up to that sexy body everyday for the rest of his life.

Scroll through the gallery to see all the Kardashian-Jenner sisters' raciest belfies!