Everyone has experienced moments of wanting to behave poorly just for the sheer pleasure of acting totally without thought for the consequences. Maybe you wish you could tell people exactly what you think of them, or steal something expensive from a wedding you don’t think the unpleasant bride and groom deserve. Most people, however, don’t actually act on those impulses, which is what sets apart Jimmy and Gretchen of FXX’s “You’re the Worst.”

The show is a romcom about what happens when narcissistic one hit wonder author Jimmy and also-narcissistic publicist Gretchen fall in love. The show’s second season, which begins tonight, examines what happens when two such wildly immature people fall in love and try living together. “They’re very much themselves with each other, and I think that’s very important in any relationship, no matter who they are,” says Aya Cash, who plays Gretchen, of the duo’s off-kilter love story.

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“If you’re smart, you’re probably unhappy, is I think what they would say. It’s funny, there are things that happen in their relationship, that I would be like, if that person did that to me, it would be over,” she explains. “And it doesn’t even hit them. And that’s what makes them work. They’re just perfectly suited to each other.”

Getting to play such darkly honest people comes with its own pleasures, says Chris Geere, who plays Jimmy, and refers to him as "the voice of unreason."

“He says and does things that I personally, and I think a lot of people in life, would love to say or do, but social politeness restricts us from doing that. So just to be that voice has been something brilliant.”

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That doesn't mean they're so toxic as to be unrecognizable. "I do feel like we get reactions from fans all over the country and all over the world now, feeling like, oh yeah, I know these guys. Because everybody has that disaster friend, who you want to just be around all the time because they’re so exciting and fun, and they also just destroy everything," says Cash.

They may eventually start to face some consequences this season, though. Gretchen, whose partying lifestyle has generally been something of an asset in her career as a music publicist, will find some minor issues. “There’s a rap feud this year, that she has started. She started the rap feud as a publicity thing and it takes on a life of its own. So that’s a consequence. It just sort of blows up in her face and she has to reel it all back in," Cash says.

Geere, meanwhile, warns that there are dark times ahead for them. “We go to a real dark place this year. Halfway through the season. I’m calling it the fifth character, comes in. Some information is given to us, and the rest of the series is about how [the whole cast] deals with that new thing,” he says.

But despite all the darkness, the show is at its core pretty romantic. The two of them do love each other, after all. “There is a sweetness to the show I feel like, even with all the darkness. I mean, they do find each other and they do want to be together and they do try, sometimes, to change and to be better, even if it fails,” says Cash.

“The tone of the show is not obvious, so we’re allowed to play with silly, pratfall physical comedy scenes one minute and then before we know it, we’re crying and doing something heartfelt,” adds Geere. "They don’t have the emotional capacity or intelligence to deal with the simplest of things, but they both want the relationship to work, so they have to find a way to cope with these things, and that’s really sweet, and it’s lovely."

Though they're both living out a romantic comedy onscreen, Cash and Geere have slightly different attitudes. "I wasn’t ever a big romantic comedy person. I like a lot of different things. I mean, I like comedy, I like drama, I like scifi. I love everything. I watched all of '12 Monkeys' this year. But I was never like, God, I just love love. I love relationship movies. I was never a big wedding person. My parents have multiple divorces between the two of them," Cash says with a laugh. 

"Chris Geere is like the romantic comedy queen. One of his favorite movies is 'How to Lose a Guy in 10 Days,'" she reveals. "He has no shame about it."

"She knows me well," admits Geere, who praises Richard Curtis as a particular favorite for "Four Weddings and a Funeral."

"That’s what got me into acting in the first place. You know, beautiful love stories with some brilliant jokes thrown in. I’m a bit of a softie, really," he says.