Eriko Nagai

Eriko Nagai (永井 慧理子, Nagai Eriko) is the younger sister of Kei Nagai. She is a human. Due to not having much debut in the manga, not much is known about her except that she holds resentment towards her brother for not becoming a doctor to treat other people but rather for his own sake. She claims that Ajin's shouldn't be treated as humans. Otherwise, Eriko seems to care about those close to her, and seemed the most sympathetic out of the Nagai family. Her brother. When they were younger, she asked Kei why did their puppy have to die and she was upset when they called the dog just a piece of defected merchandise. Kei tells her that's just what happens with sick things. She wonders if all people die when they are "defected". Even earlier on, she seemed to notice that Kei was doing everything for his own benefit rather than others. She holds resentment to him for being selfish and holds no sympathy for him when she discovered that her brother is an Ajin. She thinks that they deserve severe punishment. Kei doesn't hold close regard to his sister and barely, if ever, thinks about her well-being later on in the story.