Miko is a typical high school student whose life turns upside down when she suddenly starts to see gruesome and hideous monsters. Despite being completely terrified, Miko carries on with her daily life, pretending not to notice the horrors that surround her. She must endure the fear in order to keep herself and her friend Hana out of danger, even if that means coming face to face with the absolute worst. Blending both comedy and horror, Mieruko-chan tells the story of a girl who tries to deal with the paranormal by acting indifferent toward it. [Written by MAL Rewrite]

Kind-hearted Himuro-kun is unfortunate: when in deep concentration, stressed, or flustered, he involuntarily creates blizzard conditions for himself and anyone in his vicinity. During one such incident on the first day of his new job, Himuro-kun encounters the beautiful Fuyutsuki-san, who helps him break out of his nerve-induced ice. As it turns out, Fuyutsuki-san is his new coworker. At the office, the cool-headed Fuyutsuki-san offers simple and rational solutions to Himuro-kun's icy dilemmas—everything from helping him garden without freezing his plants to ensuring he does not melt during their tropical work retreat. Every time Fuyutsuki-san does something kind for him, the tempest of emotions he experiences inside embarrassingly manifests on the outside. As a result of the frequent snowstorms, Himuro-kun's feelings for Fuyutsuki-san are impossible to hide. Even though Fuyutsuki-san is unfamiliar with love, Himuro-kun remains determined to repay her kindness and warm her heart in any way he can.

Office worker Yoshida has been crushing on his coworker, Airi Gotou, for five years. Despite finally scoring a date with her, his confession is promptly rejected. Drunk and disappointed, he stumbles home, only to find a high school girl sitting on the side of the road. The girl, needing a place to stay the night, attempts to seduce Yoshida. Despite rejecting her advances, he nevertheless invites her into his apartment. The next morning, the girl, introducing herself as Sayu Ogiwara, reveals that she has run away from Hokkaido all the way to Tokyo. During her six-month spree, she continually traded sexual favors for a roof over her head. Yoshida, however, remains unswayed by her seduction. Instead, he has her do a different kind of work—one that entails washing dishes and doing laundry. And so, a touching relationship between a heartbroken adult and a runaway high school girl begins.

Under the tutelage of the great demon warlock Romberg, Ike grew up with knowledge regarding an ancient advanced civilization that once ruled the land. Coupled with his innate talent in magical arts, this upbringing allows Ike to quickly rise in the Demon Lord's army ranks, leading his brigade to consecutive victories against humans. However, Ike has a secret—he is a human himself. Despite knowing all too well the consequences if this information is ever to leak, Ike is willing to face such immense danger to achieve his goal: find a way for humans and demons to coexist and stop the war that has been carried on for far too long.