Nyx's Things

It was a manhwa. The main characters meet in high school. Gong was a total nerd, canonically ugly with glasses and all. Su was the cool guy, played sports. Backstory on them, Gong had a good childhood, has a supportive and loving family and an older brother who cares, but Su had it rough, he was the product of an extra marital affair, him and his mother were kept hidden by the father, father was abusive (if I remember correctly)
Now the story: They meet in school, idk how they met but Su started to take Gong's gym jacket before going to play soccer. Gong had crush on Su, so he would give his jacket, no questions asked. They started talking and their relationship developed. Then, Su's mother dies(?), and he didn't go to school for a while, Gong grows worried. Later when Su comes back, their relationship develops.
Another twist, they "make a friend", the girl starts following Su around, the girl has a cousin/brother who lives abroad.
Something happens and Su runs away. In foreign, Su meets that cousin/brother outside of a party, they hook-up, it turns into a relationship, a toxic one with a lot of abuse towards Su.
When Su finally runs away, during one of their "off periods", he comes back to Korea, he meets Gong in a reunion, they reunite.
I remember the story but I don't remember the names of the character or the title