Max is a young aspiring writer in London, who does freelance work for a literary magazine, has had some short stories published, and is working on his 1st novel. He is inspired by some interviews with graduate students about being gay sex workers for money, but he is too conscious about possibly appropriating their voices, so he decides to go into the business himself, ignoring the irony of most 1st novels being autobiographical.
This he does under the name Sebastian, posting pictures online of his bare torso, but with his face obscured by his cellphone. He gets customers, and some call him back for more encounters. But his sex work starts interfering with his job at the magazine, while his publisher / editor is trying to shape the novel into a "marketable" story.
I do have a couple of minor quibbles about the script. While there are multiple sex scenes (with no cast members' members showing), they seem to be all straight-up penetration, No oral, no hand jobs, no spanking with a magazine or other kink. The other is the sequence where Sebastian is on an overnight assignment, has drunk too much, but still manages to sneak out of bed to immediately write down his activities, given that his research is for a work of "fiction", and inaccuracies / omissions / embellishments are fair game.