Jessie J "doesn't mince her words", musician B.o.B has said.
The American rapper - whose real name is Bobby Ray Simmons Jr - has only compliments for the Voice judge, who he collaborated with on the chart-topper Price Tag.
Bobby, who joined the singer on stage at BBC Radio 1's Hackney Weekend to perform their hit, said backstage: "Jessie J is really organic, she's really natural. She says what she is thinking - she doesn't mince her words, she just says it how she thinks it."
The duet on stage in Hackney was only the second time the pair had performed the track together.
"We're always in different countries. It's just crazy. The life journey that an artist takes is always different, and we are often on other parts of the world," B.o.B explained.
His experience with Jessie J has made the rapper open to working with other British talent. "Anybody from Tinie Tempah to Adele, or Leona Lewis," he said.
Having collaborated with the likes of Bruno Mars, Paramore's Hayley Williams and Eminem, Bobby - whose second album Strange Clouds is out now - doesn't mind who he works with next.
"I enjoy working with everybody because I always learn something from each artist, whether it's Nicki Minaj, or Ryan Tedder or Lil Wayne or Taylor Swift," he said.
"Obviously the biggest collaborations I have done are with Bruno Mars and Hayley Williams. I'm getting really good at these collaborations."