She went from keeping things on the DL to going all out!

Kourtney Kardashian sexed it up in a super low cut black dress to hit Poppy nightclub with boyfriend Younes Bendjima last night, and the reality star seems determined to prove to everyone that she's still young and hot. Her man wore some unfortunate camouflage pants, but we forgive him because he's easy on the eyes.

What started out as a casual fling has morphed into something more serious in recent weeks, and we doubt Scott Disick is happy about it.

"Kourtney is having a ball with Younes, he’s exactly what she needed after the hell she went through with Scott [Disick, 34] — he’s like a breath of fresh air. They’re keeping things pretty casual still, and just having fun, neither of them want to be in a a serious committed relationship right now, so it’s perfect," a source dished to Hollywood Life.

"Younes hasn’t met the kids, and Kourtney doesn’t want to introduce him to them at this stage, but if things were to become more serious between them then obviously she would. Right now though, Kourtney is just enjoying letting her hair down, and being someone other than just a ‘mom.’ Dating Younes has given Kourtney a much needed new lease on life, she didn’t realize just how much all the drama with Scott had been bringing her down, until now," the source added.

She seems happier than she's been in years!