This is Pure Fucking Filth! by Sean Hawker
Fetish sex workers are sacrificing their worst punters to something inhabiting the basement of the Blue Waffle brothel. It’s growing larger and it’s insatiably hungry… This surely won’t end well for anyone.
This new novelette is the second in the HAWKMAN series of humorous, gruesome stories from the Brit that Simon McHardy called “an extremely funny cunt.”