North and Penelope are the tiniest BIG fans of Khloé Kardashian's new book!

Khloé Kardashian found the most ADORABLE way to promote her new book.

The Strong Looks Better Naked author shared this pic of her nieces, Penelope Disick and North West, on Thursday and upped the cuteness factor with this caption:

"I can't stop smiling when I look at this photo! I love my little ladies!! They were so excited and kept screaming "KoKo!" "KoKo!" North calls me "KoKo Loco""

OMG, we can't stop smiling either! While the girls might be too young for this book, Penelope's mom, Kourtney Kardashian, often shares photos of her picks for story time with her kids.

Booking good, girl!