«References on Request» by Claudia Kirk

Dane is broke. He has a crappy job at a bar, an apartment which he shares with three housemates who never do the dishes, and no car. On his long walk home from work he spots a flier in the window of an expensive looking house, which he thinks might be his ticket to a better life. “PA desperately required. Generous remuneration. Please deliver CV to front door.” Maybe his luck is about to change. He has never been a PA before, but how hard could it be?
When he goes to apply for the job a beautiful blonde – Shelly - answers the door. She looks young, and Dane still isn’t exactly sure what she sells, but whatever it is, she’s good at it – this house looks amazing, and she is clearly not hurting for cash. To his surprise, she offers him the job.
He gets the hang of it quickly, although exactly what all her clients are buying is still a mystery. Shelly depends on him more and more, and he gets pulled deeper into her world, eventually moving into an apartment adjoining hers (“with a pay rise, of course” she explains. “Since you are basically on call now.”) It all happens so fast he can’t stop to think, and when she asks him to help her flirt with one of her clients to close a big contract he doesn’t have time to pause and explain why that might not work.
“Not looking like that, of course” she says, sizing him up. “I’ll get you some outfits.”
Dane expects a suit, so he’s surprised to discover he’s dressing up as a beautiful, leggy brunette, ‘Dana’. He and Shelly could be sisters. “Just follow my lead” she explains. Turns out he is better than good at this bit – all his years tending bar makes him a natural when it comes to flirting with clients. But Shelly keeps raising the stakes, and before long she’s convincing Dane to spend more and more time as Dana to keep the job – and what’s more, Dana is starting to like it.