I knew something wasnt right with that seat !!!
All fixed now with genuine subaru foam from mortsters sti rear bench seat bargain and much comfier ,,, i redid the repair in the foto but thicker and bigger so now it feels comfy and no ironwork digging in my leg ,,, itll do till i find a seat base at a good price or buy an electric carving knife and shape a whole bolster from my foam stock