Airheaded yet straightforward Ayuha Samaru yearns for the "concept" of love, but it never seems to work out. Including her most recent attempt, she has confessed seven times, only to face failure time and time again. As she wallows in the hopelessness of her situation, her friends try to comfort her, but the problem is that they are in blissful relationships of their own.

But then, Samaru meets Yoshitaka Hiromitsu, the substitute homeroom teacher. He is young and handsome—but also painfully blunt. He is unafraid to tell Samaru her faults, and yet, at the same time, quick to offer advice of his own. His frank kindness sparks Samaru's interest, and she can't help but fall in love. But is this just a passing fancy spurred on by her desire for romance?

Sensei Kunshu follows the ditzy student as she tries to catch the eye of her teacher, who can't help but tease her in return.

Volume 1: Hirunaka Shikkaku (Crossover one-shot between Heroine Shikkaku and Hirunaka no Ryuusei)

Volume 6: Ore-gend

Volume 7: Pocchari Matsuko

Volume 8: Heroine Shikkaku Bangai-hen, Heroine Kunshu