My Psycho Stepson and me

Lesly was just your typical kind of sadistic high school gym teacher, having her idyllic life disturbed when she was taken away by this strange butler, who informed her about her being the true heiress of a fallen family. 
That wasn't all; he was asking her to sign the papers to marry a husband whom she had never met before.
Normally, she would have run away and reported them to the police—if it weren't for them threatening her with the (for her) most important hostage.

On her first day in the villa of her new husband, she barged in on her stepson, entwined with a brunette girl, not stopping the deed just because of her presence.
Clearly a psycho.

Next was the husband, who enticed her with money if she stayed for a year, slept in his bed, and played his wife. 
Lesly decided to go through with it for the good ol' money - however, after being introduced properly to her psycho stepson with ravishingly handsome looks, she had a feeling that things in this house would develop in a dangerous direction.

And she should be proven right.