Kim Kardashian sexy bikini PHOTOS, Kanye West's fiancee flaunts post-baby bump cleavage in racy Instagram selfies, hotter than younger sister Kylie Jenner? [POLL]

Kim Kardashian loves showing off her sexy bikini body on Instagram. But this time, such stunning images come with a catch...

Because Kim K's younger sister Kylie Jenner recently flaunted the same exact swimsuit!

Earlier this week, Kanye West's fiance posted:

kimkardashian: "Quick swim before the Dash party!"

North West's mama eventually admits:

kimkardashian: "Yep stole Kylie's bikini...she's not getting it back."

Wonder what the infamous "KUWTK" teen must think of her older step-sis stealing her skimpy black bikini?

Check it out:

kyliejenner: "Oh haaayyy."  

Pretty hot-and-steamy for 16.

So let's hear it, Mstars fans... which sister rocked the sexy bikini look better?