There’s a lot about Blaine’s family and past experiences with bullying (this fic was written before blaine’s family was introduced, before Blaine and Kurt started dating in the show).
At some point, Blaine and Kurt get into a fight. Blaine tells Kurt to tell someone or he will. So Kurt tells Finn, but Finn doesn’t know what to do about Karofsky, and Blaine gets mad at Kurt for dodging the problem. They make up eventually, though I can’t remember if they ever get romantically involved. Karofsky ends up getting arrested after Kurt tells his father.
This is what I remember from the fic, though i don’t remember the title. It was posted years ago, so I don’t know when it was deleted.
*edit* Found in comments