The 2015 ESPYS - Arrivals
Credit: Jon Kopaloff/FilmMagic

At this point, we're not sure what Kylie Jenner has more of: hair colors or black bikinis.

The 18-year-old reality star took a break from racing Ferraris with her dad for some pool time at her 2.7 million dollar mansion in Calabasas, Calif., and posted a series of sexy photos in which she wears a strappy black God Save Queens bikini and unveils a mop of short, dark hair (a big difference from the "ashy dirty blonde" fall look she debuted earlier this month). We hope she wore sunscreen, because that suit looks like it could cause some seriously crazy tan lines!

The youngest Jenner smiles beneath a pair of black aviators in another photo, which she captioned "HAPPY." And because no photo session of Kylie's would be complete without a pic or two of her famously pert backside, the star also included a snap showcasing just how revealing the bikini is from behind.

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