Zaibatsu Fukushu: Aniyome ni Natta Moto yome e

Yukiya, the second son of one of Japan's leading Ise zaibatsu, is the child of a mistress. He was raised while being persecuted by his relatives. After leaving home and becoming independent, Yukiya meets the woman of his destiny, Erika, and for the first time in his life, he feels "happy." The two then get married, and he thought their happiness would last forever... However, Erika will do anything to get what she wants. In order to make the Ise zaibatsu her own, she becomes pregnant with Yukiya's older brother, Masayuki's child, and remarries him. Persecuted by his family and betrayed by his beloved wife, this "cuckolded husband" swears revenge on the Ise zaibatsu from rock bottom! (Source: MyDramaList)