In the ABC series, the actress plays New York City party-girl-come-con-artist Chloe. She scams her new roommate, small-town girl June (Dreama Walker), who moves to the city for her dream job.
''I've never seen a sociopath who's a female, and it's just so delicious," she told New York Magazine. "I'm so honoured to be the first one, if I am.
"I just love that she has no filters, and marches to her own drummer. She drinks, she has sex, she parties, and those are all really fun things to play. I love that she's part of the great digestive system of New York City.
"And I'm not playing myself, I'm not playing the friend, I'm playing a force of nature. I could probably never find a role as good as this."
The show also stars Liza Lapira, Michael Blaiklock and Eric Andre, as well as James Van Der Beek, who plays himself.
Don't Trust the B---- in Apartment 23 debuts tonight (April 11) at 9.30pm ET on ABC.
Ritter can also be seen in the comedy L!fe Happens about two best friends who deal with one's pregnancy.
Watch a sneak peak of Don't Trust the B---- in Apartment 23 below (US only):