White Ruffle Bedding Twin XL.
Flat sheets pass the sheet but the corners are "flat" or without pockets. Usually, you will find a pillowcase equipped with twin bed sets as usually only one pillow is used in twin beds. You can find ruffle bedding twin this with various styles.

Black Ruffle Bedding Twin

Cream Ruffle Bedding Twin

Cynthia Rowley Ruffle Bedding Twin

Grey Ruffle Bedding Twin XL

Pink Ruffle Bedding Twin

Purple Ruffle Bedding Twin

Ruffle Bedding Twin XL

White Ruffle Bedding Twin