The story takes place in an age where "Ajin" (demi-human), more casually known as "Demi," have slowly started to become accepted into human society....

Takahashi Tetsuo, a biology teacher at Shizaki High School, has been fascinated with "demi-humans," beings with characteristics that differ just...

Machi Kyouko is a dullahan, a demi-human with roots in Irish legend whose head and body are separate, and one of only three of her kind in the whole...

Succubi are demi-humans that arouse sexual desire in men and cause them to have obscene dreams. One such succubus, Satou Sakie, is extremely careful...

Kusakabe Yuki overhears some girls saying mean things about her. Gossip is not an uncommon problem among high school girls, but Yuki is particularly...

Yuki has become a bit more optimistic, thanks to Hikari and Machi. She's learned to trust Tetsuo a bit more since what happened last time, and has...

Keeping his promise to Himari, Tetsuo visits the Takanashi household to talk to the sisters' parents. Though the twin sisters' names differ by only...

As she's walking through the school building, Sakie spots a beautiful blond-haired boy sitting on the floor, crying and hugging his knees. He says...

The midterm exam score rankings are posted. While Himari and Kyouko earned high ranks, Hikari is scolded by Tetsuo for getting three failing grades,...

Sakie the succubus is spending her evening at home alone, ranting her troubles to her teddy bear, when she receives a call from Ugaki. Sakie knows...

Dullahans are demi-humans whose heads are separate from their bodies. Naturally, Tetsuo is intrigued by the unique traits of dullahans, but Kyouko is...

Tetsuo has offered to work with the girls to figure out how Hikari and Yuki, who don't handle heat or sunlight well, can spend summer in comfort. But...

Summer is finally here! Hikari pays another visit to the biology prep room to cool down, and while she's there, she asks Tetsuo for permission to...