Mayu, a female college student, is the daughter of a wealthy family and was raised with too much love, which may have led to her being a little too obedient. The university she attends is a prestigious school, so her parents allow her to live alone, thinking she won't attract any bad people. However, Mayu has a boyfriend named Kawasaki. Kawasaki is actually a potential member of a yakuza gang, and has been approaching Mayu under the orders of his older brother. Caught in Kawasaki's clever trap, Mayu becomes a "tribute" to the yakuza bosses who appear one after another, and falls into depravity...