Use Me as a Substitute and I Will Disappear on My Own Initiative. Why Are You Crazy?

[Substitute + sadomasochism + wife chasing crematorium + the heroine will never forgive] In order to repay my kindness, I promised to marry Uncle Cheng, a playboy from his family who was suffering from cancer, after helping me in the orphanage and encouraging me to become a postdoctoral fellow. Cheng Xing actually took a liking to me at first sight and promised to protect me for the rest of my life in front of my father's hospital bed. I thought I had met the happiness of this life, Until one day, When I was on duty at the hospital, I met a strange female patient. She asked me many strange questions, I thought she was a resentful woman who was not liked by her husband. She pestered me to add WeChat, and from her circle of friends, I saw the family heirloom that should have belonged to me on her hand, but mine had been authenticated and replaced with a replica. Only then did I realize that my lover had been using me as her substitute...