During a scorching heatwave, son Akira inflates a pool and invites his mother Rumi, who is drenched in sweat while cleaning, to cool off with a bath. But she refuses, saying it's embarrassing if the neighbors see, and instead stays on the porch to relax. Akira becomes captivated by her appearance, and soon the two are playfully splashing each other. Noticing her nipples becoming visible through her wet clothes, Akira hungrily latches onto her lewd nipples, licking and sucking the dripping sweat as he passionately takes her body. In the warm, humid air, their parent-child bond deepens into something new.