The 30-year-old socialite - who is due to marry the basketball star later this summer - explained despite not initially wanting to enter into a serious romance, she quickly realised the sportsman was "everything" she ever wanted in a partner.
She said: "I thought he was cute, and he gravitated toward me because I was so anti-relationship at that point. He wasn't used to that.
"I knew he was The One. Often in relationships, you try to mold yourself into someone you think the guy wants. But with Kris, I was totally myself from the get-go. And he was everything I'd ever wanted in a man."
With the couple believed to be planning a wedding in August, Kim admitted she doesn't see the point in waiting to take their relationship to the next level.
She added to Cosmopolitan magazine: "When you know you want to spend your life with someone, why wait?"
The brunette beauty is applying the same logic to having children, and recently confessed she is hoping to start trying for a baby at the end of the year.
Kim said: "I'm sure at some point in the next year I'll want to have babies, so I have to get into my best shape before that.
"Maybe we'll start trying at the end of the year. After the wedding."