Ryuichiro Isaka, an editor working at Marukawa Bookstore, a publishing company owned by his parents, is a spoiled rich kid who joined the company due to family expectations, despite his aspirations to become a writer. His senior colleague and caretaker, Kaoru Asahina, had been taken in by the Isaka family at a young age due to certain circumstances and has been by Ryuichiro's side ever since...? "Junjou Mistake" depicts the past and present of Ryuichiro Isaka, the executive director of Marukawa Bookstore, and his capable secretary, Kaoru Asahina.
親の経営する出版社・丸川書店に勤める編集者の井坂龍一郎は、作家を目指しているものの家の体裁が理由で就職したワガママお坊ちゃん。その先輩編集者兼世話係の朝比奈薫は、幼い頃訳あって井坂家に引き取られて以来、ずっと井坂の側にいるが…？丸川書店専務取締役の井坂とその有能な秘書・朝比奈の過去と現在を描いた「純情ミステイク」が登場！
