Elite salaryman Haruo and his wife Ryu live a quiet married life. However, Haruo's brother-in-law Toshio, who lives with them, has become a listless and unmotivated man struggling to find work after being laid off. With Haruo away on a business trip, Toshio finds himself increasingly troubled—not just by his job search, but by the alluring presence of Ryu as he sees her sensual figure in their daily interactions. Living in close quarters with Ryu, who dislikes air conditioning, their sweat-drenched bodies brush against each other, drawing them into a hot, erotic intimacy.