Alternative sitting space

This is probably a different ask but I had to move a full sized mattress out of my room and put it in the kitchen so the person could pick it up the next day. They never came and it is just me so hard to move. So it sits. But my cat absolutely loves it! My older cat is mean to her sometimes and she feels safe up on top of it. She climbs up it and sits there 80% of the day. I cannot continue to have a mattress in my kitchen though. Any other creative ideas of what I could put in there instead? She never liked the wall perches that I put up. I had a cat tower that went to the ceiling but the mean cat would climb up that too after her. She never goes after her on the mattress. I hate to take away her safe place but it cannot stay there.