My Girl (2005)

Gong Chan is the wealthy, unattached heir to a large company. Having lost both his parents, he is devoted to what remains of his family, particularly his ailing grandfather. After deciding to cut off his only daughter after disapproving of her marriage, the old man is plagued with guilt since the couple was killed soon after he lost touch. By chance, Gong Chan meets a woman who resembles his lost aunt and is inspired to use her to fulfill his grandfather's last wish. The woman, Yoo Rin is the daughter of a compulsive gambler and is constantly on the run, so when Gong Chan offers her this opportunity, she cannot afford to refuse. After Yoo Rin moves in with the family, Gong Chan finds himself drawn to her and a forbidden attraction springs up between them.

Source: TMDb