Promiscuous and obsessed with sex, Ryo Emoto has spent almost his entire life in the pursuit of pleasure. By his side since high school is his best friend and roommate, Yuuji Akanishi—a fellow nymphomaniac. Forming a brotherhood through their unrestrained sex life, the two have been engaging in threesomes for as long as they can remember.

Their nightly exploits follow a routine: after the charming Akanishi ropes in a loose woman, Ryo is introduced with the prospect of a threesome, and they then head to a hotel to have sex. However, one night, an unfortunate accident occurs during fellatio, and Ryo's penis is put out of action. As a benevolent friend and sympathetic pervert, Akanishi offers to help Ryo achieve sexual stimulation through other means.

With Akanishi opening his eyes to the wonders of anal and the prostate, Ryo is able to achieve gratification even with his damaged goods. He starts to develop an addiction, but as he begins to become more aware of Akanishi, he realizes that things aren't so simple between them. With their pasts coloring their actions in the present, the darker motives and emotions of these two sex addicts will soon unravel before their very eyes.