Burger Sofa by Teixeira Design Studio.

"The “Burger” sofa is a conceptual exploration on how 4 cushions (seat, arm and backrest) could be aesthetically squeezed through a unique belt consisting of 2 wooden bands that seamlessly embraces the arms curvatures and a leather strap that adds the enough pressure and flexibility to fit the cushions. The idea was to design something that could be easily assembled without the need for screws but at the same time could appear to have a safe and comfy appeal. This could also work with a 2-seater version and be a fun product while playing with the cushions and materials."

https://teixeiradesignstudio.com/work/burger