Akutsu Masatora is a demon who has infiltrated a high school in the human world. His goal is to find candidates to aid Hell in the fight against their natural enemies, the angels of Heaven. Assigned a seat next to Lily Amane, another student who transferred here not long ago, Akutsu falls prey to her beauty and decides to recruit her to his cause. But there's more to Lily than meets the eye, and Akutsu not only finds himself an accomplice to one of the very enemies he is supposed to defeat, but he also might have developed feelings for her.

When Nashiko Jippensha's mother kicks her out of the house for being too loud, the high school girl needs to find a new place to hang out with her friends. Luckily, Nashiko's father owns a closed-down mahjong parlor that is perfect for her needs. While cleaning out the place, Nashiko discovers a talking bird who introduces himself as a mahjong spirit, encouraging her to try playing the game with her friends. Realizing that they enjoy the game immensely, Nashiko and her friends decide to continue playing and enjoy the new space they have to hang out.

Twelfth season of .

Araji Tomobishi gets caught up in battles among powerful individuals after reuniting with his former friend Mataka Asamine. Meanwhile, the shadow of a colossal demon appears...?!