The pair starred as high school sweethearts Rachel Berry and Finn Hudson, respectively, in the musical comedy series, and Lea looked back on her time on the show alongside former co-stars Kevin McHale and Jenna Ushkowitz on their new "Showmance" podcast.
After re-watching certain moments from across "Glee"'s six seasons, Lea commented: "The moments that made me so emotional were not anything that ever has made me emotional before about the show."
"One of them was when (Cory) took (Kevin) out of that port-a-potty. There were so many moments that you see the whole arc of a character for a whole season in one moment. Him taking (Kevin) out of that bathroom, and you see (Cory's) heart. Oh my God."
Kevin also said that the scene was one his "most memorable parts" of filming the pilot.
Lea dated Cory for several years after meeting on set in 2009, until he died at the age of 31 of an accidental heroin overdose in a hotel room in Vancouver on 13 July, 2013.