A man who failed his university entrance exams is now a ronin student. He wants to concentrate on studying for the exams, but his neighbor, a gal, is partying wildly every night. No matter how many times he warns her, she gets angry. Finally, the ronin man's patience runs out and he begins his revenge. He parties wildly until the morning, and when the woman returns to her room after seeing the other men off, he attacks her from behind. "Hey, gals are good at cowgirl position, right? Move your hips more vigorously." Thus begins a cowgirl gangbang party for the ronin students who have gathered to see the gal.