ideas for a low wall in a niche behind the kitchen sofa

[stugfar]

Hi, hoping for ideas from others on construction and design. The family is requesting a wall in the niche behind the kitchen sofa that serves as a backrest. The niche is 130 cm wide and 15 cm deep. The sofa is 45 cm high. The wall in the niche is plasterboard, probably single-layer. Turn-of-the-century house, so

The simplest solution might be to frame a structure with a vertical stud in the middle and some panel on it that is painted the same color as the wall, and perhaps a wooden shelf as a top, say about 40 cm above the sofa seat. But I thought perhaps you on the forum might have clever suggestions?