"We had a lot more fun this time round," Selman told us. "The first collection was a lot purer, about finding pieces that Rihanna felt were missing from her closet. There is a real concept to this one. I can't give too much away, but we travel so much and experience so much of the world. We're very lucky to do so and that definitely inspired us. The idea of sports uniforms and masculine vs feminine is something we evolved from last season too. There was a lot of pressure with our debut - this felt more relaxed."
Rihanna is perhaps unexpectedly hands-on when it comes to her designing projects - she and Selman are in constant contact with each other, whether via text or face-to-face, to discuss inspirations and themes. They both come to meetings with sketches and ideas.
"She has a very strong point of view and is very precise - I think I'll keep those sketches she gave me forever," Selman laughed. "There's a lot of back and forth between us, but we're very simpatico with one another - we vibe."
However, designing for winter presented a new challenge for the duo - they both grew up in sunnier climes (she Barbados and he Texas), and dress accordingly.
"The way I approach winter style is to layer up summer clothes and Rihanna does the same," he said. "But there are coats and sweatshirts - those pieces were key. It's a little more refined."
One item Rihanna is more au fait with is a good party dress - and she's created several for her customers to dance in come Christmas. The range will arrive in stores on September 12.
"She loves going out, that's her thing," said Selman. "She really wanted to create dresses that girls want to party in around the Christmas season. The fit and silhouette is very important to her. She knows what she's talking about."
It remains to be seen whether or not Rihanna will show the collection during London Fashion Week as she did for spring/summer 2013, but both she and Selman loved their initial February catwalk outing.
"We were both so honoured - it was mind-blowing," he said. "I don't think it sunk in until afterwards. The energy backstage and from the crowds out front was incredible. When we were waiting to take our bow she started jumping up and down and screaming. I was more stunned - it's a yin and yang thing."