Rika "Queen of Sex" Kurokawa
About
Rika Kurokawa is Komaki's schoolmate but is two years older than her. Rika is the other main female character of the story.
She gains the nickname the "Queen of Sex," from Tsurumi, due to her habit of having sex with anyone who asks her for it. She doesn't seem to care about anyone other than her teacher Aoki-sensei.
This unwavering trust will soon leads to her getting hurt as her teacher then forces her to have sex with many bad people with whom he had large debts. This led to her suffering through a horrible rape.
The reason for her slutty behavior is eventually found out to be due to an alien inside her which led to her developing an acute sense of touch. This causes her to enjoy things much more than normal people but also leads to a lot of pain and disgust if she dislikes the sensation. This heightened sense once led her into a dark mental state and even close to death.
Tsurumi and Komaki save her from a bad experience she faced and later become friends with her. She soon falls in love with Tsurumi and uses the pain she felt as an excuse to hold his hand to be closer to him.
Numa-sensei describes her to be purely evil and purely innocent at the same time when Numa-sensei discovers that Rika tried to get Komaki to suffer the same abuse she felt due to seeing Komaki as a romantic rival.
Numa-sensei proposes to her to become the mother of his child, but she still seems to have second thoughts about it.
Hana says that Rika and Shijou do not have the concept that males and females are different as they treat and threaten both genders the same way.
At the start of the story, Rika describes her favorite feeling as the sensation of the air she feels while lying naked on the school roof.