Seth Rogen didn't want Rihanna to sing in the new film This Is the End.

The popstar has a cameo in the comedy, which also stars Seth, James Franco, Paul Rudd, Jason Segel and Jonah Hill. Seth was eager for Rihanna's appearance in the movie to feel natural, and didn't want to force her to perform a tune. However, he was relieved when the singer arrived on set eager to have fun with co-star Craig Robinson.

"I didn't want to ask her to sing," he told MTV News. "Me and Evan [Goldberg, director] were like, should we ask her to sing? First, we didn't even want to put her in the scene with Craig singing, like it's too much - Rihanna singing - and we didn't want to ask her to sing. So Craig thankfully sang at her and she sang back... She was so nice. Very low key, low maintenance."

Craig couldn't believe how friendly Rihanna was from the moment they met. They had a great time shooting scenes together.

"She did a little move like, 'Come on Craig.' But she couldn't have been sweeter. I had never met her before but the first thing she did was hug me," he explained. "She just improvised and was fun. It was nice to be playing and singing with Rihanna."

Seth went on to joke that Craig overstepped the mark with Rihanna while on set.

"You told her to take her panties off," he laughed.

However, the raunchy remark did little to shake Rihanna's confidence and she promptly told him what she thought of his idea.

"Yeah, and she told me f**k off," Craig quipped in response.