Characters » Sakagami Kouya
In an interesting demonstration of the series' fictional world's rules and expectations of society, Koya wears fake cat ears despite not being a virgin. Yamato often teases her about it, particularly because Yamato doesn't try to hide her status. They lost their "ears" to each other. Shortly, after they first met, Kouya slit her wrists just to "know how it would feel", since zeroes can't feel pain.