A while back, Theifs could be detected by fake square knot ties, the usefulness for this knot is also getting out of it, since the rope easily slips from the other one. So when your freind ties your hands behind your back, this is the knot to use.
Step 1: Materials Needed
perferably you want two ropes, but it can be done with one rope.
Step 2: Loop Holes
make two loops
Step 3: Under
put one loop under the other loop
Step 4: Over the Loop
now you take the ends of the loop that is under the other loop, and take the ends and put it over the other rope.
Step 5: You May Now Slide the Rope
notice that, the rope easily slides, but looks like a square knot, good for magic