"I can't do another name-based one," he says. "It was a mistake to do the name-based ones in the first place."
Formerly a high school mathematics teacher, Ranganathan began performing comedy on the side before going full-time in 2012. The early days in which he was still teaching were a "nightmare", he says, especially when his older students started turning up at gigs.
"You can't really command any sort of authority in the classroom if they've seen me absolutely tank at some pub with eight people in the room."
Turning to comedy full-time worked in his favour; he's now a Bafta nominee, who has performed in front of Prince Harry. He regularly contributes columns to the Guardian and has fronted two seasons of his own BBC series, Asian Provocateur.
He also used to rap, which he says he wasn't any good at - "If anything I sort of diminished my credibility." So what made him settle on comedy?
"I've had a few jobs, and my concern was that I just get bored of anything I do. But comedy - you never really feel like you've mastered it, so I can't imagine I'm going to get bored of it.
"I could go back to teaching, but because of the stuff I've said about teaching I probably couldn't get a job anyway."
As for his first New Zealand gigs, Ranganathan says he's approaching them with a mixture of excitement and trepidation.
"You're always nervous about how a completely new audience is going to take you.
"Obviously if it doesn't go well, I'll never come back. But I'm looking forward to giving it a go."
LOWDOWN:
Who: Romesh Ranganathan
What: Irrational
When: Friday, April 28
Where: SkyCity Theatre