[Ciel very, VERY secretly wants to be taller but achieving that through the use of pulley is probably not the way he wants to do it by so yes, thank you Sebastian's thought process, for thinking to pull apart the constraint instead.
He wiggles his toes, scoots his feet around in his dainty shoes and concludes that yes, the constraint is most definitely on the outside.]
Perhaps if you unlaced my boots. [They're his favorite pair here but he's willing to sacrifice them for his freedom.]