black on the front, purple on the back, and a spider or bat embroidered on the bum
https://weenotions.co.uk/images/Spider%20and%20Web%20large.jpg
https://weenotions.co.uk/images/C5473.jpg
OR
purple front, black back and a ghost or pumpkin on the bum.
https://weenotions.co.uk/images/E1995.jpg