Tags :: §Shibari forms
Crotch rope can be either stimulating or sadistic depending on how it's tied and who it's tied on.
If it's aesthetic and you don't want them to be thinking too much about the feeling of it then you probably don't want to tie it too tight.
If you want it to be stimulating, then there are a few things you can do which may enhance that, though YMMV greatly between individual partners:
show a good video good technique for rolling the overhand knot precisely where you want
If you haven't done crotch rope with them before, be aware that some people just don't like the feeling of it or might need the ropes placed very precisely to make it work.