He Lies Within the Sea (eremika)

Five years ago, mermaids were discovered to actually exist, but the world's response was to hunt them down for their beautiful, unusual scales and create products like clothing, accessories, and such out of them. Mermaids could turn into humans and roam the land, but they had scales covering their ankles, showing that they were mermaids. Mikasa always thought the idea of mermaids was interesting, and she was ashamed that the humans mistreated them so badly. One day, she notices one of her classmates wandering around the lighthouse atop a hill over the sea near where she lived. She recognized him as Eren, a student who transferred recently, and she sees him lunge towards the cold, wavy sea below.