Here's the thing.. Su Yi has loved Ruoxing since she was a teen. They used to be penpals. Su Yi's parents never loved her so her letters were a big help growing up. However, when she wanted to go to Ruoxing's school to confess, she saw Ruoxing with her "girlfriend" and gets heartbroken. Su Yi knows her girlfriend and even meets her during college abroad so when the gf says she can't wait to go back to propose to Ruoxing, Su Yi decides to go back and proposes to Ruoxing through the blind date. The person in Su Yi's heart has always been Ruoxing but she doesn't know that. Su Yi also doesn't know that Ruoxing's gf is fake, a stalker who Ruoxing cut off. Su Yi was always cold and distant since she felt bad for taking Ruoxing's gf's place as her wife. And Ruoxing feels bad for not being Su Yi's love.

Su Yi's behavior totally changed and everyone notices it but they are happy for it. Only few know it's because she has amnesia. The reason for her sudden change is because Su Yi has always hidden her feelings due to her trauma caused by her parents. Later on, another accident happens which makes Su Yi's mental health plummet to the floor and also regains her memory. She becomes distant once again feeling terrible for "using" Ruoxing and Ruoxing feels heartbroken thinking Su Yi is distant because she remembers and "met" her past love.