After a long absence, Shunsuke returns home at the urging of his older sisters, only to learn of their rare condition marked by intense sexual desires stemming from a disease. Their big boobs and heightened needs prompt him to provide relief through the pleasures of blow job and facial moments, as well as creampie intimacy that aids their recovery. He commits fully to improving their health with these caring gestures in the hentai series by studio T-Rex.