Make some turf seating, as they used to do in medieval gardens, by banking up and sodding a 'bench' form. This could be all around the perimeter, or just in one corner.
If you plant some low-growing scented creeper like one of the many thymes, or some chamomile, you will have a sweet-scented
place to sit.
Build up a wall at seating height, with bricks or stone, back fill with soil, and add grass seed or carpet with sod.
:-) sounds like a wonderful place to hang out, doesn't it?