border or band on the edge of a dress
裍 refers to a decorative border or band sewn along the edge of a garment, such as a hem or trim.
裍 combines the clothing radical 衤 with 困, which likely provides the sound. The character is rare and its exact historical development is uncertain.
The left side 衤 (clothing) is wrapped around the right side 困 (a boxed tree). Picture a tree trapped inside a box, and the clothing radical sews a neat border around the edge of the box to keep it contained.
For コン, imagine a con artist sewing a fake designer border onto a cheap dress: con -> コン, and the clothing radical 衤 is the dress getting the fake trim.