Kylie, 18, and the Canadian singer-rapper, 22, were first spotted at a comedy show in Hollywood last month and have been growing close since then, reported US magazine.
"They're talking and texting nonstop. He's as into her as she's into him," a source said.
"They were introduced by Drake. And they were all over each other at his party, even though Kylie initially thought that this would be a rebound," the source added.