Kozue Morishita is a student at an all-girls school who practices rhythmic gymnastics. Her teacher, Nikusuke, persuades her to take part in a secret training method intended to enhance her gymnastic abilities. This method requires her to wear dog ears and a collar and involves sexual activities with the teacher conducted on the grass behind bushes.

She has light brown hair and red eyes. She stands 1.45 meters tall and weighs 36 kilograms, with body measurements of 70-52-73. Her blood type is AB and her birthday is December 27.