Game of Thrones story editor Bryan Cogman talks about the second season, and gives some insight into Tyrion Lannister, reveals why they changed Robb and Daenerys’ stories, and why the character of Ros was created for the show.

In a lengthy interview with Think Progress, Cogman reveals why Ros (who doesn’t exist in the novels) was written into the show and what her purpose is:

Ros was originally Red Headed Whore Number 1 in the pilot. […] In King’s Landing, for the most part, you’re seeing things through the eyes of the nobles, and Ros gives you a window into the class of people they take for granted. [In] season 2, there’s a character in the book named Alyaya, who we didn’t end up keeping. We knew that Ros would serve that function in the latter part of the season where Cersei thinks she’s caught Tyrion’s girlfriend but actually has caught Ros and doesn’t know who she is. It’s one of those things that kind of happened by accident. You’re finding different ways as you’re plotting the season to examine different traits and characters.

He also discusses why Tyrion Lannister isn’t completely a good guy:

Tyrion of all the Lannisters, has the most compassion, the most empathetic worldview. But he’s still a Lannister. He’s still going to keep the class below him at arm’s length…Being a Lannister, he still uses his position when he needs to, and can behave selfishly. He’s not necessarily a white knight kind of hero. I certainly think that yes, there is that kind of empathy and compassion for prostitutes, but there’s also a real distrust.

On how they worked out Robb’s story for the second season, since he didn’t play a big part in A Clash of Kings:

We always new we wanted to keep Robb more front and center. In the book, he’s absent except for the first chapter. He shows up in the third book married. We knew we wanted to keep Robb and Catelyn’s tenuous relationship at the forefront. We knew the portrayal of Walder Frey and the marriage to a new woman would be part of the story. Originally, it was Jeyne Westerling. In the books, Jeyne is tending his wounds, Robb gets a terrible piece of news, and they spend the night together dealing with his grief, and he marries her after that. [In the show], it isn’t just about making an honest woman out of this girl, it’s that he falls in love and chooses love over duty, which is an ongoing choice which is brought up again and again throughout the series. Maester Aemon tells Jon Snow that love is the death of duty. And I think that was something that they really wanted to explore, that it was a relationship that developed, and that we would see develop, and Robb would make the choice.

Cogman also touches on the big changes to Daenerys’ storyline in Qarth and why they felt the need to change it up:

Xaro in the series is very different from the Xaro of the books. Dany’s storyline in Qarth was beautifully written in the books, but it’s not really plot-driven. We needed more for her to be up against in this season before she gets to the House of the Undying, so [we added] the conspiracy between Xaro and Pyat Pree… we made the decision to make [Xaro] an outsider, and that was a very conscious decision that he would not be from Qarth, so he could identify with her right off the bat and she would trust him, because she figures “He’s not of this crowd, either.”…I think it’s more about the story and what serves it best.

Game of Thrones fans will definitely want to check out the whole interview on Think Progress, in which Cogman goes into depth about these topics and more.