Abandoned by Everyone, the Hated One Becomes the Group's Favorite

Su Mu was adopted by the Su family, but they treated him worse than an animal. They had only taken him in because he was a bone marrow match for the eldest Su son, who had leukemia. On the day he came of age, after donating his bone marrow, he was kicked out of the Su family. That's when he met Pei Jinsu. (Su Mu is always sickly, and Pei Jinsu is his salvation. A sweet romance with physical hardship but no emotional angst. Su Mu suffers from depression.)