Like pimpin', working with Rihanna ain't easy.

Produce Labrinth, who worked on 'Lost in Paradise,' a track on RiRi's seventh album (and first Billboard Top 200 No. 1) 'Unapologetic,' went on record to say that the process of working with the oft topless singer is "difficult."

Ooh, that had to sting.

Exactly what part of the process was difficult was not revealed by the producer. Was it the singer's work ethic? Or lack thereof? Her attitude? Her antics? Was she tardy? Did she not respond to direction? Was she disinterested? Did she just do her own thing? Was she a diva? A brat? It could be any of a number of things. But Labrinth declined to share specifics or the nitty gritty of their interaction.

Labrinth said (quotes via Gigwise), "I've finished working with Rihanna on some of her album ... it was difficult but we got through it." When pressed to clarify, he left it at that. "It was just difficult," he reaffirmed.

We're beyond curious as to what was tough about being in the studio with the chart-topping diva. Perhaps RiRi will respond by throwing some shade on Twitter or maybe she will use her favorite social media application Instagram, and post a pic or a note?

Watch the Rihanna 'Diamonds' Video