Jay-Z is like a "wise uncle", says rapper J. Cole.

Last month, J.Cole went to number one in the US with his debut album Cole World: The Sideline Story.

The rapper was the first artist to be signed to Jay-Z's Roc Nation label. He admits that that the Hard Knock Life star put him through his paces.

"I see Jay-Z more like a wise uncle than a father figure," J. Cole told British publication The Independent. "When my album went to number one, he was pleasantly shocked. I could hear it in his tone. It was his record label's first number one album. It's just as much a win for him. Jay-Z really worked me hard; he'd say, 'This song is a nine. Bring back a ten.' He pushed me harder; he never let me actually settle. That's a reason why the album took so long to come out."

Jay-Z was wary about signing any rappers to his new label. But when he heard J.Cole's heartfelt lyrics, he knew he wanted to be his mentor.

"I wanted to sit out the wave of the 'club song', the 'girl song' until hip-hop found its voice again," Jay-Z explained. "I wasn't going to sign any rappers, but J. Cole changed my mind in a few bars it felt new and familiar, naive and strong, vulnerable and heartless."

J. Cole has already hit the headlines for reasons other than music. The 26-year-old was caught up in the Rihanna sex-tape scandal this summer. Adult magazine Hustler claimed to have obtained explicit footage of the pair, an allegation which they both denied.

The rapper admits it was a difficult time.

"People were like, 'Rihanna has sex with who?'" he sighed.

The two of them got to know each other after he supported Rihanna on the North American/ Caribbean leg of her Loud tour. The duo then filmed the promo for his single Can't Get Enough together.

J. Cole is now a little wary of talking about his friendship with the Rude Boy singer, but he confessed she taught him a thing or two about fashion.

"I learnt to have show outfits. I used to worry about what I was going to wear on stage. Now I wear my J. Cole jacket," he smiled.