Brother's Wife, Homecoming Wife Swap, A Dream of Mature Beauties Co-starring!! Anno Yumi, Miyabe Ryoka JUX-565

To celebrate their parents' golden wedding anniversary, the eldest son, Tetsu, and the second son, Hiroshi, return to their hometown. Tetsu's wife, Yumi, and Hiroshi's wife, Ryoka, also gather together, much to the parents' delight. However, Hiroshi has always harbored feelings for Yumi, and his relationship with Tetsu, who is cold towards her, is strained. Ryoka, feeling resentful that Hiroshi doesn't see her as a potential partner, also feels this way. Then, Hiroshi secretly approaches Yumi, while Ryoka, expressing her dissatisfaction with Hiroshi, begins to seduce Tetsu. A secret couples-swapping orgy begins.