,
"N I T E S W I M" she captioned as she posed with a tiny black bikini and shades on.
"She finally used the pool we love to see that," one user commented.
"I was thinking the same thinggggg," wrote another.
"Is there jacuzzi in it" joked a third, referencing Kanye's reaction, and the former couple's inability to play Marco-polo, metaphorically speaking.
KOURTNEY, KRIS & KHLOE'S NEW DIVES
Kourtney, 42, bought her $9M Calabasas LA mansion in 2014 from football player Keyshawn Johnson for $7.45M then renovating it - as seen in the latest trailer for her family's Hulu show.
She once shared the home with ex Scott Disick, with whom she also shares kids Mason, 12, Penelope, nine, and Reign, seven.
She's since moved on with Blink-182 rocker Travis Barker and fans speculate Kourtney could announce baby number four with her fiancé any day.
Her spacious backyard boasts a large new swimming area and spa-like retreat that proves sometimes simple is the way to swim.
There's plenty of space to roam with large hills separating the pool from the patio.
Light brown lounge chairs are placed at the edge of the rectangular pool, allowing Kourtney, her kids and fiancé - and possibly future additions - to soak up the sun in Tuscan-inspired style.
Meanwhile, Kris Jenner, 66, is also building side-by-side $37M twin Hidden Hills LA mansions with Khloe Kardashian, 37 and Kris' lap pool is coming along swimmingly.
Though the mother-daughter duo have been called "house-zillas" throughout the construction process, making "constant changes" to the home design.
Kris's mansion will be the larger of the two, boasting 16,000 square feet while Khloe's hits a whopping 10,000.
They both have pools and hot tubs with Khloe's pool looking like an enjoyable plunge with a built-in jacuzzi near the front.
Though amid the Tristan Thompson cheating scandal, her move was "delayed" with her pool and home remaining empty.
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