The Woman of Brother.

Misaki, who is not satisfied with her husband, feels surprised satisfaction every night when she sees a scene in which her husband, Chae Sung shares her forbidden love with her brother Sana. Then one day, Misaki, who actually met Chae Sung, the main character in the dream, falls in love with him and has a happy time. However, when he finds out that he has entered the drama [woman of his brother's] world without knowing himself, Misaki becomes confused.