The wife had incest with her father-in-law because the husband was infertile

It's been several months since my beautiful daughter-in-law, Akari, started living with my father-in-law, Shigeru's house. Taking advantage of the time I lived together, I started trying to get pregnant, something I tried for a long time but with little success. The results of the examination at the infertility clinic turned out that the husband's sperm had a problem... One day, the husband went on a business trip for 2 nights and 3 days and then decided. Akari and Shigeru are alone under the same roof.