Ōkuchi. Or some seriously big pants.
Worn as part of a noh costume, these are hakama that have a large hump formed in the back (made stiff by alternating thick and thin wefts.). They’re sufficiently large that a multi-person operation is required to put them on, and a Y-shaped piece of wood inserted in the koshi-obi is necessary to hold them up. Often they’d be worn by warriors, priests or people of high-class.
Osada-san displays the Ōkuchi.
Osada-san displays the bane, the Y-shaped wood which helps to hold the Ōkuchi up.
Bane. The Y-shaped piece of wood.
The actor has stepped into the Ōkuchi, and the sash from the back is drawn up over the bane, and then pushed down under the koshi-obi.
The sash from the front of the Ōkuchi is handed round, under the sash from the back…
… and then is passed round to the front again.
The sash is then tied in the back.
The hump is hefted up in the back to rest on the bane, as the sashes are pulled down through the koshi-obi and then tied in the front.
The hump in the back of the Ōkuchi can be seen – the top being folded over and wedged down against the bane as the sashes are drawn front for a final tie.