I've been thinking of constructing a set that could be clamped to my coffeetable. I think if part of the lee's anticipation is watching three sets of clamps screwed into place -- plus the possibility of incorporating ceiling mounted restraints above the couch -- or simple wrist restraints along the back of the couch itself (it's away from the wall to maximize access) -- that could be a nice part of the experience.
Woodworking is minimal, barely rises to the dignity of the word. A pair of sturdy tempered 2x6s cut to measure would probably do it. Gauge the distance between the holes to ensure access at the groin -- if the thighs end up too close together you risk losing an element of fun. Then measure twice and cut once (bearing in mind any kind of lining you're planning to use).
You don't need to purchase any grand fancy saws when a simple coping saw will do -- you're only cutting out four semi-circles, after all. That step is 1-1/2 to 2 hours work tops, and it's part of the love you're putting into the project. A well-made pair of stocks should serve you in good stead for as long as you own them.
Sand all surfaces smooth, even if you're planning to line or upholster the holes. For finishing work you can get as fancy as you like, but you may wish to apply any stain or varnish at this stage of the project. If one side ends up looking better than the other you can better gauge presentation for any photos or videos you might want to shoot.
Upholster the holes however you're planning to -- duct tape can be made to look quite presentable, or bring in upholstery nails and cloth or leather depending on your level of ambition. Then when you've figured out how much lining you're going to use and how much space that's taking up, attach a sturdy hinge and locks and now it's ready to mount. Bed frames are awesome, benches are good or, in my case, I'd screw the base to a mounting frame that could then be clamped easily to my heavy coffeetable and removed when I didn't have company. Or rather, fun company.
Options: O-hooks above the holes to tie back the toes. Additional rattle chains at the sides to add a nice aural component to the experience as the lee thrashes about helplessly.
And make sure you can reach an outlet with anything you might wish to plug in. Enjoy! 🙂
P.S. -- I manage to actually build a pair I'll post a photo. 🙂