Seto (セト) is the second member of the Mekakushi Dan.

Seto is a kind-hearted person that gets along well with others. When he was a child, he grew up without parents and had trouble understanding others. His only friend ended up being a stray dog, which he later tried to save from bullies. That event led to both of their deaths and Seto's encounter with the Kagerou Daze, where he gained his eye ability. Not long afterwards, he and Kido were assigned to Room 107 of the orphanage together because their eye abilities disturbed everyone else, and Kano joined them not long afterwards. Seto, who still grieved over Hanako, frequently cried and got in trouble with Kido for speaking politely to her. Because he had difficulty controlling his ability, he would frequently and accidentally read others' thoughts and emotions.

In the current day, he is much more cheerful and has achieved his goal of becoming physically strong. He is very loyal to the Mekakushi Dan, as he will obey Kido's commands without much hesitation and will physically sacrifice himself to protect them from danger without much hesitation.

Eye Ability: Stealing Eyes

Seto's eye ability allows him to hear the thoughts of others, includes animals. However, animals cannot necessarily understand him because he cannot speak their language. When he loses control of his ability, which he often did as a child, he can hear the true thoughts and emotions of everyone, even strangers, in a wide area. When used to its full potential, it can read a person's memories and even their experiences from past routes (lives).