It is unprecedented for me to begin a review with a taste and decency warning, but I feel I must in the case of Channel 5’s The Sex Business: Working from Home.

This was the second instalment of three exploring (a good word for it) the underbelly (I mean that literally) of contemporary British sexual tastes. I can do no better than repeat here the cautionary words of the show itself: “Not for the faint-hearted. Be prepared throughout for full-fronted nudity, graphic scenes of actual extreme sexual activity, including dangerous consensual sexual violence, offensive language, and drug usage, all of which may disturb some viewers.”

Ho, ho, I thought, you ain’t gonna shock me. I’m a journalist. I’ve worked in Westminster. I’ve seen it all. Well, how wrong I was, and if you don’t wish to read any further, then I quite understand.

The documentary opened with the memorable imprecation: “Resume the position, shit stain!” This was issued by Mistress Dita, a dominatrix from Hull (and hell, actually) to a “client” prone on her bed. If a bum crack could have pleaded for mercy, that would have been it.

I was going to say you can probably imagine what happened next, but I’d be surprised there wasn’t permanent damage to his meat and two veg when they eventually emerged from a weird Perspex vice.

Repulsive as all that was, I found myself attracted to Miss Dita: not because of her (literally) ball-busting attitude (this is, after all, a lady who has the slogan “no torture equipment stored in this car overnight” slapped on the backside of her Vauxhall Vectra). No. I would in fact pay good money to just listen to her never-ending delivery of “zinger” (not a euphemism) lines.

So if you were to turn up to her suburban vision of Hull, and hand over £200 to “have the shit kicked out of you”, you would be duly warned, with the matter-of-fact air of a Kwik Fit fitter or a jobbing builder, specifically that “there’s gonna be some serious ball-busting and we’re gonna leave some marks – is that doable?”.

Dita tells us that, in the terms current in her chosen occupation, “85 per cent of my work involves some sort of fiddling experience up their crevice”, often as not also accompanied by “needles, enemas, and blood-letting”. Things get done to a urethra (I did warn you) that have no place outside a genitourinary unit.

Fortunately for all, Dita insists that her clients undergo a check on their pacemakers and sign a disclaimer so that, she says, “I am fully insured”. Not all that reassuring, on balance: To a degree, you place your life, as well as your tackle, in Dita’s hands.

As for the lady herself, she seems disinclined to form a conventional relationship: “The dude I’d want would have really big bollocks, ironically enough, and not be submissive and not be afraid of the job.”

In this respect Dita was much like the other featured escorts, balancing private lives and their job: Michael, a lithe 58-year-old gay companion; and Hollie, in her early twenties and a more fragile personality, as we discovered when she told us about her eating disorder and a recent abortion (Hollie’s pregnancy was the outcome of a rare act of intimacy in her private life when the usual precautions were missed). Hollie adds that she simply wants to “protect my heart”. She has sex between three and 10 times a day, at £150 per hour.

One hopeful, I think, development in this branch of the sex industry is the growing revenue that can be generated from what you might call auxiliary activities, ie without any human physical contact at all. By that I mean selling used undercrackers online and the like. I don’t feel quite able to share with you the indignities some of Michael’s socks suffered before their dispatch to paying customers, but he says that he made £6,000 clear in a few months from his “personalised” merchandise. There also seems to be a thriving sideline in Amazon wish lists: Dita had recently received some expensive (about £1,000), fearsome-looking red leather boots with unusual dual-purpose heels. (Go on, guess where they might end up.)

The film made clear that escorting is draining (in so many ways), though Michael optimistically pointed out that there are male escorts out there in their eighties. I’m glad I managed to watch most of it, flinching occasionally, but not a single frame could be judged “erotic”. Hollie asked us, rhetorically: “Having sex isn’t glamorous, is it?” That, I think, is the sex business all over: it hurts, in more ways than one.

One year on from the Manchester bombing and, thanks in particular to an unusually honest official report, we know all that we usefully need to about it. Still, the accounts in BBC2’s Manchester: The Night of the Bomb still had the power to upset, as when a teenage survivor says: “I saw my legs on fire and then I was unconscious”.