[Ryuuta] Seiyoku ~Sei ni Oboreru Onna-tachi~

A sweaty game of marital musical beds unfolds as a sister-in-law secretly slips into Masumi's place in her brother-in-law's bed, her soft curves and heavy breasts making the deception deliciously easy. Elsewhere a married woman works the man beneath her with composed, sweat-drenched grace, noting how relaxed his face looks before treating him to a cowgirl ride that grows less professional by the minute. When a bunny girl greets a weary husband with a flustered "welcome back, Master," the whole arrangement finally admits its name: swinging.