"Fuki" is found in a kimono in which one does not make ohashori (tucking up a kimono and holding the tuck in place with a cord) and trails the hem on the floor like the uchikake, and one of its purposes is to prevent the hem of the clothing from clinging to the feet by making a thick part around the hem.
「ふき」は打掛のようにおはしょりを作らず床に裾を引く着物に見られるもので、裾周りに厚みの有る部分を作ることで足に衣装がまとわりつくのを防止する目的がある。