We Were Old Friends
I had two roommates in college. They had gone to high school together, while I had gone to a different one. We discovered that I had taken an art class with them back in high school at a university that was in a different state and a different city.
Therefore, four years prior to meeting them both, we had been in the same room every Saturday for a few months without even realizing it. Not only that, but only one of us was in college to study art. Story credit: Reddit / isherflaflippeflanye