The mother-in-law, who can't resist her son-in-law's big penis every day, is tempted by Aya Ueba (JUQ-475).

Mariko Sada, a mother staying at her daughter and husband's house, lives a lonely life, never seeing her husband, but she's not the only one feeling lonely. She discovers her son-in-law masturbating alone late at night and, feeling she can't ignore it, seduces him, unaware that it started as a way to satisfy herself, and she now craves her son-in-law's enormous penis all the time…