For those interested, this is how "the Chair" was pitched. Alex then made it (or had it made) from square tubing (?).
There isn't the "electric buzz" sfx cut in under Cry's suffering, but her straining against her bonds and the creak from the straps and the chair are very sexy, IMO.
The original idea came from a Ian Fleming James Bond novel where he is tortured in a seatless chair. There is some kind of arrangement where his naked cock and balls are punished. Think the anus was still off-limits in general (non XXX) fiction.
If it's good enough for 007, why not the GIMP World?