Hentai "OVA Tsuma ga Kimi ni Natta Wake" is based on the eponymous visual novel from Arcsoft Studio released in April 2017. 

The main character of hentai lives a carefree family life for several years and nothing disturbs him. However, in recent days he began to notice that his dear wife became too "beautiful" and this strange feeling of anxiety haunted him. He decided to hire a private detective and follow his wife. Soon the detective brings bad news and leads material that proves treason...