Kylie Jenner, Pregnant Kim Kardashian (Plus Kourtney, Khloe, Kendall!) Coordinate at NYFW Parties in Skimpy Outfits: Photos

The Kardashian-Jenner sisters, Kourtney, Kim, Khloe, Kendall, and Kylie, partied at NYFW in coordinating body-baring outfits -- see the many photos here. Credit: James Devaney/GC Images

On Mondays, they wear black! All five of the Kardashian-Jenner sisters, Kourtney, Kim, and Khloe Kardashian, plus Kendall and Kylie Jenner, stepped out for New York Fashion Week parties on Monday, Sept. 14, in coordinating body-baring outfits. Click here to see more photos from the group's NYC outing.

Kourtney, 36, Khloe, 31, Kendall, 19, and Kylie, 18, all hit the youngest's Galore magazine party at downtown hot spot Up&Down. The cover girl and honoree of the evening, Kylie, stepped out for the occasion in a black ruffled minidress featuring a sheer-paneled polka-dot blouse that revealed a sliver of her abs.

A slimmed-down Khloe wore a completely see-through black crocheted dress with mesh cutouts, and protectively held Kylie's hand as they were photographed leaving the club. An inside observer tells Us Weekly that in person, Khloe looked nearly naked in her outfit — although the youngest Kardashian sister had no cares in the world as she twerked to music inside Up&Down.

The observer adds that the party was filmed for Keeping Up With the Kardashians, and Kendall — the sole sister in red — was having a blast dancing to tunes. Eldest sister Kourtney, meanwhile, had a more low-key time inside the venue and spent most of the evening with close Kardashian pal Jonathan Cheban.

The now-single mom of three looked gorgeous on Monday night in black leather pants and a black bandeau bra. Kourtney showcased her impressive new body (abs included) for the outing, and added a sleek touch to her look with a satin black bomber jacket.

Noticeably missing from the bash was Kim, 34, who attended a "Real Family Dinner" with her husband, Kanye West, in another part of town.

Like her siblings, the pregnant again reality star opted for a super risqué outfit, baring her bump in a black dress featuring racy cutouts stemming from her belly button up to her cleavage and neck.

Kim posted photos from inside the intimate dinner, including snaps with Courtney Love, Riccardo Tisci, Carine Roitfeld, and the Hadid sisters, Gigi and Bella.

Can't get enough of Us? Sign up now for the Us Weekly newsletter packed with the latest celeb news, hot pics, and more!