She is an Angel or a Demon

Choi Yun Tan sent goons to harass her and when she was almost helpless, he came out of nowhere and pretended to save her.

She went into trauma because of this incident and when she was in this vulnerable state he proposed to her family and seeing his love, sincere efforts and the fact that he saved Park Hye Min from the goons Park family accepted his proposal and got her married off to him trusting that he genuinely loves their daughter and is sincere towards her although he lacks in money and power they didn't mind as the they thought the person is good.

Park Hye Min did not care about anything anymore, the way she was harassed by those goons disturbed her to her core, although they did not do anything extreme to her, their mere faces were enough to give her nightmares. That incident took away her soul.

When her parents got her married to Choi Yun Tan she didn't care about anything and got married to him. For Choi Yun Tan marrying her was like marrying a dead person as she never behaved like a normal human being and was lost in her own world and he too didn't care about it as he just wanted to leverage on this marriage to get more money and power.

In the initial 1 year of the marriage he behaved like an ideal husband in front of the Park family and got the Park family to invest in a lot of business ventures he created. The Park family too started showering him with a lot of money assuming that Park Hye Min is happy with him and this is the least they can do for their daughter.

One day Park Hae In got to know about Choi Yun Tan's philandering ways and after finding out about his affairs, Park Hae In, Park Hye Min's brother couldn't take it anymore and came to his house to take away his sister. He was against this marriage since the beginning but had to give up in front of his family and seeing his sister's condition he thought it was the right thing to get her married to her savior. But now he won't let his sister be in a marriage with a cheat anymore.

Park Hye Min directly went to his sister's room and asked her to come with him. She was still like a dead log but she followed her brother and as they were about to leave Choi Yun Tan who just came home blocked their way.