She will probably need a guy walking beside her to steady her with his hands on her shoulders so she does not lose her balance (or get TOO weak in the knees and buckle in a faint.)

For an extra touch of cruelty, a daub of heat-releasing liniment can be applied to each knot. To get the fiery ointment off her clit, she will have to rub herself vigorously against the long stretch of dry rope between knots.

Of course, that only makes the clit more sensitive for the next knot.