It could be the refreshing lack of diva behavior. Or maybe it’s the gossipy conversations matched with unassuming thick-framed glasses. The harmless sarcasm no doubt helps. Whatever the factors, in the three years they’ve known each other, Nikki Glaser and Sara Schaefer have perfected a trademark banter so successful that it’s earned them a second season of their very own MTV talk show, Nikki & Sara Live—and all the Diet Dr Pepper they could ever have hoped for.

You’ve probably never heard of them. Their faces don’t show up in any tabloids, and their names don’t appear in juicy headlines about sexting scandals. But in the cutthroat field of late-night television, Glaser, 28, and Schaefer, 35, have managed to carve out a prized foothold—in its freshman season, the show was ranked No. 1 in its time slot across all networks with women 12 to 34, a prime demographic target for MTV. More impressive: in a genre defined by snark and monologues packed with petty one-liners, they’ve managed to do it all without being mean.

“There are some people who think if you’re not being mean, you’re not funny, and I disagree with that. If we’re calling somebody a nobody ... It’s like, we’re nobodies,” Schaefer says.

Well, they can be a little mean. The women’s comedy certainly has a sharper edge at times, and they intend to keep it that way. “We’re not trying to skewer anybody unless they deserve it, in which case we’ll go for the jugular,” Schaefer jokes. (Sort of—she’s well aware that MTV prizes the show in part because it can pull in a younger crowd.) “Here’s the thing about Sara,” Glaser makes a point of noting. “She’s extremely scared of getting in trouble. She’s very careful about that sort of thing, which is good because I tend to talk before I think a lot of time. So we meet in the middle.”

Luckily, both women know how to craft a joke, having worked the comedy scene in various parts of the country for roughly 10 years. Glaser’s highlight reel includes stand-up on The Tonight Show With Jay Leno, Conan, and two seasons of Last Comic Standing, while two-time Emmy winner Schaefer was previously lead blogger for Late Night With Jimmy Fallon and did stints on Best Week Ever and Inside Amy Schumer. The two have also hosted successful weekly podcast “You Had to Be There” since early 2011.

Now they’re attached at the hip, generating new ideas for the show, which mostly revolves around the week’s pop-culture news. A team of writers, whom they handpicked before the show’s premiere last year, is there to flesh out ideas and bring fresh ones to the table. But at the end of the day, it’s Nikki and Sara’s “third voice” (what they refer to as the product of their minds coming together as one) that makes the call.

Clearly their closeness is crucial to the show’s success, but it’s hard not to wonder if being lumped together 90 percent of the time (hardly is one interviewed without the other present) has somewhat torched the egos of obviously competitive women.

“We definitely do bump heads sometimes, but we’re really good about handling it as quickly as possible by letting it out and then working on it,” Glaser says. “I’m not ready for The Nikki Show. There have been countless times when I’ve come in depressed and I’m feeling shot and want to go home, and Sara carries the weight and the energy for both of us,” she says, and adds that they possess a sort of twinlike sense for each other. “Plus, it would not be as fun, and it would be really difficult when I want to bitch about something or celebrate something.”

Schaefer agrees. “We need to act like we’re on top of this shit even if on the inside we’re freaking out. Having someone else to go through this with is really great.” She does admit that at first she was panicking about being compared to her co-host. “I was terrified before the show first started that the whole country was going to love Nikki and hate me. But it was all in my head,” Schaefer says.

Insecurities aside, the women are up front about the fact that being in the spotlight comes with a raft of pressure—and criticism. “Everyone wants the show to be a huge success and wants us to be funny, but everyone has different opinions on how we can get there,” Schaefer says.

She deadpans: “Apparently I have a snaggletooth.”

Not that they’re surprised by this. Being in front of the camera makes you more vulnerable than those behind the scenes. They’ve been in the business long enough to know that. And being part of a pair helps to shoulder the burden. “We share the hate,” Glaser says cheerfully, sipping her ubiquitous can of Diet Dr Pepper. Schaefer chimes in: “We’re also the ones getting teenagers saying shit to us online, like cruel shit. No one else is getting that. Like a 16-year-old girl calling me a c--t. When they’re like, ‘This is not funny, you are not talented, and I deserve a show more than you do.’ That’s what really hurts.”

There are ways to beat the negativity. Specifically, their tradition of standing in a Wonder Woman pose in silence for three minutes right before going on air.

With all the bad comments that come along with being the face and producers of a show, Glaser and Schaefer are both acutely aware of how lucky they are. At the end of the day, they’re happy to be doing what they’re doing, despite the demands and many directions they’re pulled in. They just want to have a good time. And what better way to challenge each other with a quick game of “Never Have I Ever”?

“Wait can this be really dirty? I know everything you’ve done, Sara.”

“Well, if you want to provoke me, that's fine."

“OK. Never have I ever had a threesome. No! A foursome!”

“Yes, it was a foursome. It was a learning experience. A great way to meet people. I’m not usually in orgies, but I did it. To be honest, it was really boring. It was just me and another person watching two people have sex and we were like what are we gonna do?”

“You can get back at me now.”

“All right, Nikki. Never have I ever shoplifted.”

“OK, so I used to shoplift clothing when I was a teen. A late teen. Like 18, 19.”

“Or like 27?”

“No! Late teens! I would just do it to do it. It was something I was going through, and then I got busted at Urban Outfitters, and I was banned from the store for three years in college. It was the worst day of my life.”