The pair had a late night out on Wednesday, starting out at a bar in the East Village around 10 p.m., where the two enjoyed what appeared to be beers and Scott puffed on an electronic cigarette.
Afterwards, they headed to a house party in NoHo around midnight for two hours. They then went to 1 Oak nightclub -- where they stayed until 4 a.m. and Scott hung out in the DJ booth with Snoop Dogg most of the night.
"Scott was hanging with this girl all night," a source inside the club tells ET. "He had his arm around her and they looked very couple-y. He kissed her a few times and was whispering in her ear with a smile on his face. She seemed very into him, but a little out of place, very uncomfortable when people were looking at her."
After the club, the two headed to another house party in SoHo. They eventually left the party at 6 a.m., with Scott going back to the hotel with his gal-pal.
Meanwhile, Kourtney's focus appears to be on getting in the best shape ever, as well as her three children with Scott -- 5-year-old Mason, 4-year-old Penelope and 9-month-old Reign. Over the weekend, she posted a sweet photo Penelope made for her.
"Missed my babies. ❤," the 36-year-old Keeping Up With the Kardashians star wrote.
"Kourtney won't be taking Scott back anytime soon. It's final this time," a source close to Kourtney told ET last week. "Kourtney is doing the best that she can to stay strong for her three children right now. Her first priority are those kids and she'll do anything to make sure they don't get hurt."
"Kourtney and Scott only text and talk when it's about the kids," another source close to the former couple told ET last month. "She still refuses to talk to him about anything else.”
Last week, she tweeted that she's taking advantage of her time being single.
"Being alone & actually sitting with our own thoughts can lead to such growth and realizations that are rare in our everyday busy lives," she wrote to her 16 million followers.
Still, in a new Keeping Up With the Kardashians sneak peek, Kourtney's obviously heartbroken when she learns of Scott's intimate vacation with ex-girlfriend Chloe Bartoli in Monte Carlo.