The slip knot is a fine invention, applied to the right
place at the right time.
It lies in the name, that it will loosen easy, so that's why it is no good i.e.
for longtime bondage. !
I illustrate the slip knot on a piece of semi-transparent plastic tube, in order
to let you see what's happening on the 'backside', and because the slip knot is
to be tied around someTHING, not around someBODY .
1/ Lay the rope around the 'tube'.
2/ Make a bend, at the short end.
3/ Pull it around the long end (once), and let the long end carry the strain. This is working best, if the strain is in a 90 degree angle to the tube.
If you pull the short end, the slip knot will loosen in
a split second, as well as it will loosen, if there's nothing pulling at the
long end, to keep the slip knot tight.
The slip knot is good for experiments, like "What happens if I tie this
rope there". You may develop bondages using slipknots, but only for testing
purposes, meaning that if you tie 2-3 slip knots, to find out what is working,
and when you find the right way to do this, replace the slip knots by regular
knots, and then you can continue the development...
This is what it looks like in the real world.