I forgot if it is a QT or not, but MC is transmigrated. The story: When MC is transmigrated into a canon fodder's body, og!body is known as a young master who only know to playing around, has a bad circle of friends, wear bad make up and following a young master/CEO (the og!story protag, who didn't like him) bcs his father told him to do so. In og!story, this canon fodder and the protag will like the same person (ML), so MC do the same. MC changes his appearance to the clean-type and not following protag anymore but ML, which result in making the protag 'miss' him. MC is haughty, I remember he buys clothes and coffee for ML. ML ignores MC at first and smth police in the first meeting. He doesn't answer to MC pursue but forbid him to hang out with MC bad friends and accept the coffee. Later it revealed that MC is picked up and ML is the missing son. MC will throw away ML and protag who start to pursue him and start a good life. Living in dorm, sell his green/yellow expensive car and get a bicycle, ignore ML who keeps show up around his dorm. Later ML insist that they could keep interacting as brother and MC is ok with that. But it is SE tho, suicide with a car crash. The family who adopted him is a mess that even ML leave them. Oh and there is a black diary book of og!body.