Foreboding music heralds their entrance. Two men in fetishist leather bondage gear, brandishing a riding crop, You might be led to expect something pretty hardcore, but the truth is quite different – Topping and Butch are just giving a new twist to an old-fashioned tradition: the light comic song.

This is G&S meets S&M – with the tweeness of the Savoy operas replaced by knockabout music hall banter, albeit of a distinctly raunchy hue. And there’s no denying that Topping and Butch are fabulous entertainers: gregarious in manner and contageous with their easy laughter, they are absolute naturals.

Topping is the senior, avuncular one; a man with eyebrows so dramatic they could form their own double act. Butch is the cheekier chump, playfully goading the audience to conspire in the breezy comedy.

Their style is old-school camp; exaggerating a sexuality outside the mainstream to the point it becomes inoffensive yet still gloriously outrageous. They have that attitude in bags, and it pervades the good-natured but risqué banter they share between themselves and with the audience.

Their jaunty signature song, Never Mind, references as many topical stories as they can – and the churn of material is impressive as they industriously keep up with the day’s news, and even earlier events in the very room in which they are performing. You can’t fault their work ethic, that’s for sure.

Like many comedy musicians, the gags aren’t always that great – they don’t aim any higher than simply mentioning the headlines then slam down a quick pun or double entendre on the subject – but the mischievous, pacy manner sweeps most of the audience along with the jolly fun.

They maintain that spirit throughout their uncomplicatedly entertaining routine, spreading their impish joy. The writing’s very disposable – it doesn’t stand up to much scrutiny – but with the duo making such a song and dance, literally, of their exuberant performance, they hope the audience won’t notice. And they don’t.

Cheery high camp isn’t everyone’s cup of KY Jelly – but if it is, you can’t go far wrong with this strangely loveable duo.