It's a Hairdressing Practice Head from a beauty parlor, that became a Tsukumogami, hating its hairstyle.
An employee threw it away but it’d come back to the salon by itself. Sakura took it to have Rinne exorcise it, but he pretended being absent at “home”, for while giving Rinne a haircut, Rokumon messed up, leaving a gap snipped in his bangs, and so Rinne didn’t want to be seen by her, so Sakura went to her home with the head, that without being noticed, synchronized itself with Rinne, forming a spirit bond, as both feel ashamed to have an awful haircut. When Rokumon came to inform Sakura that Rinne will have to be absent for a while, the head started attacking him, as Rinne was extremely mad at Rokumon, until Rinne arrives with a headband to hide his uneven bangs. Rokumon bought a hair tonic to have its hair grow back, but it grew too excessively and became black, so it’s taken back to the salon for a professional cut and dye job which seems to satisfy its anger.