The "Sicko Mode" hitmaker has been linked to the makeup mogul since April, 2017, and in February, they became parents to a daughter named Stormi.
Travis admits their relationship started as a casual hook-up after spending time together at California's Coachella music festival, but he soon fell hard for Kylie.
"We was just two kids, f**king around (sic)," he tells Rolling Stone magazine of the early days of their romance. "Maybe, like, the first week, you don't know if it's real or a fling. Then the second week you're like, 'Whoa, I'm still talking to her, she's responding, I'm responding. We ain't run out of a thing to say (sic).' And it got to a point where I was like, 'I need her with me to operate. She's that one.' "
The hip-hop star reveals their shared love of movies and their strong Christian faith helped them connect, and when Kylie, now 21, discovered she was pregnant just weeks after getting together, they realised it was "something special."
Starting a family had also been a topic of conversation between Travis and Kylie when they were "getting busy," but the MC admits he had initially hoped their first child was a boy.
"At first I was like, 'Man, I need a son,' " he recalls. "When we found out it was a girl, I was like, 'Huhhh.' But after a while I was like, 'Yo, this might be the illest (best) thing that ever happened,' " he continues. "And when Stormi was born, I was like, 'Life is fire (amazing), bro (sic).' "
Now the rapper is eager to become a traditional family by popping the question to Kylie, who he insists is "the coolest motherf**ker of all time."
"We'll get married soon," the 26-year-old shares. "I just gotta sturdy up - I gotta propose in a fire way."
Travis Scott appears on our new cover. We hang out in Houston with rap's new superstar as he meets up with Kylie Jenner, talks Kanye, spends quality time his family and much more https://t.co/owrav34I3qpic.twitter.com/KN0I6QmRy6— Rolling Stone (@RollingStone) December 20, 2018
Travis' candid comments appear to put to rest rumours suggesting he and Kylie are already secretly engaged, after the "Keeping Up with the Kardashians" beauty began referring to her man as "hubby" on social media, while he has repeatedly referenced her as his "wifey."
Their sweet nicknames for one another even had Kylie's big sister Kim Kardashian wondering about their relationship status.
"You know, I literally need to ask her (if they're engaged)," she told U.S. news show Entertainment Tonight earlier this month. "That is going to be my next question in our group chat. I think we just all think that's, like, you know, what they call each other, but I have no idea... I'll have to ask myself."