After being scolded by his boss, junior employee Kaji is comforted by his kind senior, Muramata-san. During a private drink at her home, Kaji discovers her shocking secret—a split tongue—which sparks an unexpected and passionate romantic encounter. As they begin a secret relationship, Kaji finds himself captivated by Muramata-san's seductive nature and adult composure.
Muramata-san faces intense pressure at work, but finds comfort and intimacy with her boyfriend and junior colleague, Kaji, who supports her through her stress. Simultaneously, a high school student named Hayato is approached by the popular yet timid Momose, leading to a surprising sexual awakening as they explore their bodies together.