I'm not sure that's possible. But you could have the angled panel permanently closed/drawn. Only the panel(s) on the straight rod would open and close.

Thank you everyone for your advice. @BeverlyFLADeziner What makes this living room a playroom? I don't like the accordion blinds. If I had to choose between accordion blinds or no curtains, I would go with not having curtains. @d_gw It's a radiator on the left side. @kulrn we tried to arrange the living room furniture in different angles; however, given the room size and the open kitchen, this is the best way to arrange the furnitures. @

How handy are y'all? How much work do you want to do to create an actual room for yourself? Do you have an Ikea nearby? The Kalix system is a sturdy shelving system that comes in many different size ranges and colors. https://www.ikea.com/us/en/p/kallax-shelf-unit-white-80275887/ I would get the ones that go up as far as you are able to take them height wise. Line them up across the expanse of your "space opening". Now run to Lowes or Home Depot and buy some drywall. You could also use plywood but drywall is cheaper. Prime it and paint it a nice color of your choice. Cut them to the appropriate height to close off your portion of the space and cut them to fit the angle of the ceiling. Keep in mind exactly where they are going to go because you are going to attach each piece to the back side of the Kalix pieces to create a wall with your Kalix shelves on your side for storage. You can get bins that fit the openings and use these as a dresser, storage and leave some open for book shelf display as well. If you are allowed to screw into the wall or ceilings you can use "L" brackets to really secure the drywall. Remember to leave a "doorway" to enter and exit from on your new pseudo wall. You can install a curtain rod and drapery panel across this doorway for more privacy. This can be found at Ikea too. Although not antique furniture it is more practical and will give you ample storage.

I see opportunities for a better looking room, that have more to do with lamps, bedding , art. and even an outside mounted ROMAN shade at whatever is the highest point above the window that can be same on BOTH windows. I cant fathom a reason for panels trapped behind a bed. Show the entire space from more angles, please: ) add more pictures below in the comments. There MAY even be a better furniture arrangement but no way to know unless you provide a drawing with every dimension of everything,. walls windows, door entry, closet etc.