When it came to the saddest anime scene, I was trying to decide between two scenes. The scene I didn’t choose for this one will be what I use for my answer on Day 25.
To me, the saddest anime scene comes from Fullmetal Alchemist: Brotherhood. Early on, Ed and Al Elric become friends with Nina Tucker, the daughter of an alchemist named Shou Tucker. After her father uses her and the family dog to create a chimera, Ed becomes upset by this. But… this isn’t the saddest part of it. Later, the chimera is killed by Scar, and Ed’s sadness at learning of Nina’s death is just heartbreaking. It’s especially so when Ed is in tears because he’s upset that he wasn’t able to save her. The audience learning that Nina was turned into a chimera was already an emotional kick in the gut, then seeing her be killed and Ed’s reaction adds even more pain to that emotional kick in the gut. To this day, this is still one of the most memorable moments in the Fullmetal Alchemist franchise.