Kourtney Kardashian Has Giant Heart-Shaped Booty

Kourtney Kardashian is going where she hasn't really gone before ... hogging the ass spotlight.

Kourt's down in Miami with her kids and some pals, including Hailey Baldwin. She hit the sand at the W Hotel Monday where her butt was on full display in a black bikini.

It's apparent Kourtney has belatedly read the butt manual authored by sisters Kim, Khloe and Kylie, and she's clearly absorbed the content.

For Kourt, there's her bottom and then there's rock bottom, but the latter is reserved for Scott Disick.