While diligently studying for her school exams, Kaede's quiet routine is shattered by Shinobu, a ninja-in-training in need of an unusual exam requirement—Kaede's panties. As the two clash over the bizarre request, an unlikely bond forms between them. Soon, Kaede finds herself immersed in Shinobu's ninja-filled world, complete with wild ninja parties and the eccentric Onsokumaru, a yellow, Pac-Man-like creature proclaiming himself as the ultimate ninja master.