User is Monster Kid

She always wears bottomless, and her butt is unbelievably huge. When she sits in a classroom chair, she sticks her butt out behind her, so it pushes through the gap between the backrest and the seat, leaving her anus and bright blue genitals fully exposed—it’s incredibly striking. Her butt smells really bad, and since she sits in the front row of the classroom, the smell tends to drift to the back.