In the racy shot, Tyga poses shirtless as his 19-year-old girlfriend sits on his lap, also without a top. He is pictured nuzzling his face in Jenner's breasts as she rests her chin on his head. He also has his right hand down the backside of her pants, seemingly grabbing her buttocks as he flaunts his heavily tattooed arm.
"Happy birthday baby 💋," the Keeping Up With the Kardashians star captioned the Instagram post.
Jenner also shared a black-and-white picture from the same photo session, which she captioned, "Irreplaceable 🐯." In the pic, the happy couple strike a similar pose as they share a laugh while he grips her back.
The teen reality star's sexy photos come just one day after she shared a series of equally suggestive Instagram posts to promote her upcoming pop-up shop in Los Angeles. In the pictures, she smokes a cigarette and bares her nipples in sheer lingerie while showing off her blond hair.
The couple, who quietly started dating when she was 17, have been nearly inseparable since reconciling after a brief split in May.
"The first year we started hanging out, everyone around him told him not to be with me," Jenner told Complex earlier this year. "I still get comments like, 'Don't be with him.' But we're not doing it for the public — we love each other. We need to be together at all times. We never get mad at each other, we just figure things out."
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