Hello, I don't remember the title of a manga but I still remember the plot. It's about twins (sisters), they have a male childhood friend and one of the sisters is in love with him. However she misunderstood and thought her sister and her friend were together or something like this. One day (I think it was their birthday), the sister died in a traffic accident. The MC is sad and I remembers they shared a room but they never went to the other's side (they each had a personal space). So when the sister died, the MC went to her sister's space and found a present for her and then she cried. Don't really remember what happen after this, but the MC and the ML are going out after they cleared the misunderstanding and after the MC recovered from her depression.