Nao Egokoro is one of the 20 participants of the death game, as well as a former student of Professor Mishima. She is initially timid and shy and primarily stays with her teacher Professor Mishima, whom she idolizes to the extent of wanting to stand in anyone's way if they say negative things about him. She is a very emotional and clever person, immediately catching onto the fake Reko's change in personality compared to the real Reko. She also cares about her friends, as shown when talking with Gin, Reko, or Sara. However, throughout the game, she gains immense mental strength and displays that she is no longer easily manipulated when the dolls try to obtain information from her.