MTL - Problematic Sister Fell In Love With Me

The old man pointed to the flower-like woman and said, “Call her mother from now on.” He then pointed to a flower-bud-like girl and said, “This is your sister.” My younger sister was not cute. She was arrogant, taciturn and weird, but she knew how to please our parents. She was two-faced and deceitful, but it seemed like she only treated me that way. I cared for her, tried to please her as much as I can, but she still disliked me. Until one day, I found out her secret, our relationship began to get a little bit weird… - Description from Novelupdates