This slutty bitch, Reiko Kobayakawa, ALDN-326

The father-in-law is troubled... Why can't he erase the crucial evidence? One day, he accidentally witnesses his son-in-law and his wife having sex, and he's convinced he's right. Hmm... his son's "manly" abilities are too low... So, the father-in-law decides to impregnate his son instead. At first, Reiko tries to resist, resisting with reason... but ultimately, her instincts awaken, and she becomes the "female" Reiko in front of her father-in-law. However, this scene is witnessed by her husband. What will he do? Common sense within the family is shattered, and the bond between "female" and "man" is strongly intertwined in this abnormal sexual story. What will the ending be this time?