Kouya Sakagami  

Zero, 坂上江夜

The female member of the Zero pair is known as Kouya. Prior to meeting each other, both pairs believed they were the only Zero pairs in existence. Both teams are experiments created by Nagisa at different times, with the female team likely being the first generation. Despite their unusual backgrounds, both Kouya and Yamato attend high school but go to different schools. While Kouya is reserved and serious, Yamato is able to get her to open up. They meet when they are young and trained together as Zero pairs. As they grow older, Kouya's feelings for Yamato deepen until both girls fall in love with each other. Despite trying to hide her true emotions from others, Kouya is deeply in love with Yamato and fears losing her. The thought of being separated from her lover causes her to throw up. It is clear that Kouya has had sex with Yamato, as they have a physical and romantic relationship alongside their professional roles as Zero pairs. In an interesting twist on the series' fictional world rules and societal expectations, Kouya wears fake cat ears even though she is not a virgin. Yamato often teases her about it because she does not try to hide her status.