Here's most of a tiny studio in Back Bay. It's a genuine studio, with the living area, sleeping area, and mini kitchen in one room. There's no sleeping alcove, as you can see.
As you can also see, twin beds have been cleverly concealed behind a couple of screens so they are completely hidden. Okay, maybe not.
As you can see, if you closed the louvers on those screens, the beds would have complete privacy.
As you can also see, those screens could be moved so I wouldn't have to write quite so sarcastically, but they would still accomplish very little of their intended function. And then they would tip over every time anyone walked past them, because that's what flimsy screens like those do. Because they aren't really screens. They are louvered closet doors. or shutters hinged together, or something; I don't know what.
I have no idea why anyone would want to live with those things. I also have no idea why anyone would put twin beds side by side in a studio unless the person was living with a same-sex sibling and was used to sharing a room. And even then, there is no sofa in this studio, so why not put one bed at an angle and create an L-shaped seating area with matching coverlets and lots of pillows? There may not be enough space... but in that case, I'd get a trundle bed and still make the other bed into a day bed so there's a place for someone to relax.