This is a hakama. Hakama is a divided or pleated skirt worn over a Kimono. A Japanese girl student wore a hakama approximately 100 years ago. Today, the girl student puts hakama on only in a graduation ceremony.
Uh oh, obi tied in the front? This is sure to bring a gloved hand to grandma's lips to hide her shock at the resemblance to an oiran of the pleasure quarters!